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Macuchová, Simona. "Studium aktivity enzymových a nízkomolekulárních antioxidačních systémů." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2010. http://www.nusl.cz/ntk/nusl-233305.
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Oxidative processes play important role in cell physiology and pathology as well. Balance of these processes is supplied by cooperating antioxidative systems; function of antioxidant defense systems depens on high levels of antioxidants in organism. Presented work is focused on developement and optimization of methods for analysis of important enzyme and non-enzyme antioxidants as well as total antioxidant capacity of selected types of biological material. Extractions and analyses of vitamin E, carotenoids, superoxide dismutase, catalase, peroxidase and lipoxygenase in barley and malt were optimized. RP-HPLC and HPLC/ESI-MS were used for analysis of vitamin E, phenolic and carotenoid content, spectrophotometry was used for enzymes activity analysis. A new methods for catalase and lipoxygenase activities were developed and compared with direct UV methods. Superoxide dismutase activity was determined by commercial diagnostic kit. A colorimetric method was used for peroxidase activity determination. Some kinetic parameters of enzymes were provided too. Optimized methods were used in the analyses of antioxidants in plant material - in barley and malt - in sets of samples of 6 varieties cultivated in four different locations for two years. Content of individual antioxidants differed depending on the variety, but usually were not found significant differences in the levels, depending on growing location. Perhaps climatic conditions have the greatest influence on levels of low molecular weight and enzymatic antioxidants at the specific location; oxidation processes are influenced both the quantity of moisture, both by sunlight, which induces oxidative processes in cultivated plants. The activity of antioxidants in barley caryopses is rapidly increasing during the malting process; an elevated temperature and moistness first induces activation the enzyme systems including antioxidant. In caryopsis is metabolic activity increased during which we can expect an increased production of radicals; for this purpose can antioxidant systems be activated that protect cells from damage by oxidative stress. In the second part of work optimized methods were applied in two clinical trials focused on study of the influence of exogenous antioxidants intake on metabolic and antioxidant status in human organism. In the first clinical study influence of food supplement containing polyunsaturated fatty acids and vitamin E on metabolism of hyperlipidaemics was evaluated. After 3-month supplemenation a lipid profile was improved and serum antioxidant levels increased. The second experiment was focused on enzyme and non-enzyme antioxidant levels in healthy subjects after temporarily intake of specific foods rich in antioxidants. After two-month intake plasma phenolic substances were slightly increased. Total antioxidant capacity and activities of enzyme antioxidants were not affected. Results of both clinical exeriments showed that supplying of antioxidants in natural form or in the form of food supplements does not markedly affect metabolism of healthy subjects, while in patients with chronic diseases antioxidant supplementation can positively influence metabolic status. Results of this work showed that optimized methods are suitable for analyses of antioxidant status parameters and also for monitoring of exogenous antioxidant intake.
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Jardini, Fernanda Archilla. "Avaliação da atividade antioxidante da romã (Punica granatum, L.) - participação das frações de ácidos fenólicos no processo de inibição da oxidação." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-30062008-163119/.
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Os antioxidantes de origem natural têm importância na área de alimentos, pois podem representar uma alternativa de substituição aos antioxidantes sintéticos. Os compostos fenólicos, presentes nos vegetais, desempenham importância na inibição da oxidação, A romã (Punica granatum, L.) é rica em compostos fenólicos como as antocianinas, flavonóides e ácidos fenólicos. Avaliou-se a atividade antioxidante da polpa e semente de romãs plantadas no Brasil (Pernambuco), e foi feita a obtenção dos extratos e frações de ácidos fenólicos da fruta, que foram submetidos aos testes de co-oxidação de substratos β- caroteno e ácido linoléico, em meio emulsionado, e ao método Rancimat, em meio lipídico. Também foi avaliado o comportamento cinético da atividade antioxidante para os extratos e frações de ácidos fenólicos. Verificou-se que os extratos aquosos da polpa e semente apresentaram significativa inibição da oxidação a concentrações baixas, em ambos os testes utilizados, fato atribuído à grande quantidade de compostos fenólicos presentes nestes extratos, em relação aos demais. A avaliação cinética dos extratos aquosos demonstrou que estes também foram mais eficientes ao longo do processo oxidativo, apresentando-se mais estáveis do que o antioxidante sintético BHT. As frações de ácidos fenólicos esterificados a compostos solúveis da polpa foi a fração que apresentou maior inibição da oxidação, e também maior quantidade de compostos fenólicos, apresentando uma atividade cinética bastante eficiente. Entretanto, as frações de ácidos fenólicos livres da polpa e semente apresentaram porcentagens de inibição da oxidação bastante altas a uma concentração menor. A semente da romã apresenta em sua composição de ácidos graxos o ácido graxo punícico. Este ácido é um isômero conjugado do ácido linolênico, e que constitui 58% da composição total de ácidos graxos da semente da fruta, sendo seu principal ácido graxo.<br>The antioxidants of natural origin have an important role on food science, because they may substitute the synthetic antioxidants. The phenolic compounds of vegetables play an important role as oxidation inhibitors. The pomegranate (Punica granatum, L.) is rich in phenolic compounds as anthocianins, flavonoids and phenolic acids. The antioxidant activity of extracts and acid phenolic fractions obtained from the pulp and seeds of brazilian pomegranate (from Pernambuco) was evaluated, by the co-oxidation of β-carotene and linoleic acid assay and the Rancimat method. The kinetic behavior of the antioxidant activity of the extracts and acid phenolic fractions by the co-oxidation of β-carotene and linoleic acid test was evaluated, too. It was noted that the aquous extracts from the pulp and seeds have significant antioxidant activity at slow concentration. It was possible by the high content of phenolic compounds present on those extracts. The kinetic behavior showed that the aquous extracts was the most efficient along the oxidative process, showing larger stability than the antioxidant BHT. The pulp\'s of bound acid phenolic fraction by soluble compounds was the most efficient among the acid phenolic fractions, and it has major amount of phenolic compounds. The pomegranate seed has the punicic acid on its fatty acid composition. The punicic acid is a I conjugated inolenic acid isomer.The punicic acid is present at 58% from the total fatty acids from the fruit, being its principal fatty acid.
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Barošová, Michaela. "Sledování antioxidantů v sušeném ovoci." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216231.
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Presented diploma work is focused on study of antioxidants in different kinds of dried fruits. Analyses of ascorbate, tocopherols, carotenoids and flavonoids were performed using RP-HPLC with spectrophotometric detection. Analysis of dried fruits showed high level of vitamins and phenolocs mainly in berries. High level of carotenoids was observed in dried apricots and plums. Further, antioxidant activity of dried fruit extracts was tested by ABTS method. High antioxidant activity was found mainly in dried apples, cranberries and blueberries. The biological test with yeast Sascharomyces cerevisiae D7 was used for the analysis of antimutagenic efects of dried fruits. High antimutagenic activity exhibited dried cranberries and blueberries. Most of tested dried fruits with high antimutagenic effect exhibited also high antioxidant activity as well as high content of some antioxidants. No direct correlation was found among these parameters. Last part of this work was focused on study of influence of drying on antioxidant content in two types of apples. Drying at mild controlled conditions exhibited no significant negative effect on active substance content; in some samples their concentration was observed.
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Ferdová, Jitka. "Změny aktivit enzymů v ovoci v průběhu dlouhodobého uchovávání." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2010. http://www.nusl.cz/ntk/nusl-216605.
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This study is focused on study of changes of enzyme and low-molecular weight antioxidants in different fruits during long-term storage. In theoretical part individual low-molecular weight antioxidants and enzymes are described. The main causes of fruit decay and some possibilities of fruit preservation and storage are summarized. As biological material some common fruits were chosen - green and red apples, peaches, plums and white grapes. The fruits were stored in laboratory, cellar, in refrigerator and in freezer. In freezing experiments some ways of fruit preparation and processing were tested and their influence on fruit antioxidant status was compared. Shortened storage experiment was applied on blueberries, cranberries, raspberries and strawberries too. In fruits some group parameters – total antioxidant status, dry mass content, ascorbate level, total flavonoids and total phenolics were analyzed spectrophotometrically. Individual flavonoids and phenolics were determined by RP-HPLC/UV-VIS and on-line LC/PDA/ESI-MS. Antioxidant enzyme activities (superoxide dismutase SOD, catalase CAT, polyphenol oxidase PPO and lipoxygenase LOX) were measured by spectrophotometry. The surface microscopy and cultivation of moulds from fruit surface were performed too. Influence of storage conditions on biological activities is dependent on fruit sort. Freezing is the most suitable procedure for long-term storage without significant changes of active substance content. Long-term storage in controlled temperature conditions and/or atmosphere is usable for fruits with longer storage period. In these fruits stabile levels of antioxidant enzymes are stored for relatively long time. Some of enzymes act synergistically. Enzyme activities differed according to storage phase; at the beginning mainly high SOD and LOX activities were observed. CAT and PPO are probably activated as defence systems in rippened and/or damaged fruits. Levels of total as well as individual low molecular weight antioxidants varied during storage in all sorts, generally, increased course with longer storage period can be observed.
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Alves, Adriana Barreto. "Compostos antioxidantes em polpa de tomate : efeito do processamento e da estocagem." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255267.
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Orientador: Neura Bragagnolo<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos<br>Made available in DSpace on 2018-10-03T13:46:21Z (GMT). No. of bitstreams: 1
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Previous issue date: 2009<br>Resumo: Estudos epidemiológicos têm demonstrado que o consumo de frutas e vegetais tem um efeito benéfico na redução da incidência de várias doenças como o câncer e doenças cardiovasculares. Esse efeito tem sido relacionado com a presença de compostos antioxidantes nesses alimentos, sobretudo os flavonóides. O tomate (Lycopersicum esculentum Mill.) é um dos vegetais mais consumidos no mundo, in natura ou processado, e também é rico em compostos antioxidantes como carotenóides, vitaminas e flavonóides. Os alimentos processados, frequentemente, são tidos como menos nutritivos que os alimentos in natura, devido, principalmente, ao fato de que alguns nutrientes são degradados pelas altas temperaturas empregadas. Assim, torna-se importante avaliar o efeito do processamento e da estocagem sobre os compostos antioxidantes do tomate e também sobre sua atividade antioxidante. Um planejamento experimental foi realizado para otimizar as condições de extração dos compostos fenólicos e concentração dos flavonóides em polpa de tomate concentrada. O método otimizado foi validado para as determinações de compostos fenólicos totais e flavonóides totais por espectrofotometria e também para a determinação de flavonóides por cromatografia líquida de alta eficiência (CLAE). Os métodos espectrofotométricos foram validados nos parâmetros repetibilidade e exatidão. A determinação de flavonóides por CLAE foi validada nos parâmetros seletividade, linearidade, precisão, exatidão e sensibilidade. O efeito do processamento e da estocagem sobre os compostos antioxidantes do tomate foi avaliado. Foram analisados os teores de compostos fenólicos totais, flavonóides totais, flavonóides por CLAE, ácido ascórbico, licopeno e ß-caroteno, bem como a atividade antioxidante das frações hidrofílicas e lipofílicas pelos métodos ABTS e DPPH. Verificou-se que, durante o processamento, em geral, não houve perdas dos compostos antioxidantes. Durante o armazenamento, observou-se grande degradação do ácido ascórbico, porém, os demais compostos mantiveram-se estáveis, e não foi observada nenhuma alteração na atividade antioxidante. O efeito do processamento sobre a atividade antioxidante do extrato fenólico foi também avaliado por espectroscopia de ressonância de elétron-spin (ESR) usando sal de Fremy e em sistema-modelo de lipossomas. Esses e os outros resultados de atividade antioxidante obtidos previamente foram correlacionados com os teores de compostos fenólicos totais a fim de melhor estudar os mecanismos de ação antioxidante envolvidos. A ação antioxidante das amostras de tomate, coletadas em diferentes etapas do processamento, foi testada em carne de frango processada sob alta pressão a 300, 600 e 800 MPa e armazenada sob refrigeração por 15 dias. A adição de 0,30% de subproduto (pele + semente) ou 0,10% de polpa concentrada resultou em uma fase lag de 6 dias para a formação de produtos secundários da oxidação lipídica na carne de frango processada a 600 MPa. O subproduto apresentou efeito similar também para a carne de frango processada a 800 MPa. O resultado deste trabalho mostrou que, embora o processamento e a estocagem de polpa de tomate possam ter degradado substâncias mais sensíveis como o ácido ascórbico, os demais compostos antioxidantes não sofreram alterações deletérias, e, para alguns, o processamento foi benéfico, aumentando sua disponibilidade. De forma semelhante, as atividades antioxidantes dos produtos processados foram iguais ou maiores que as das amostras in natura e se mantiveram estáveis durante o armazenamento por um ano. Além disso, o subproduto do processamento pode ter boas chances de aplicação como antioxidante em outros produtos alimentícios<br>Abstract: Epidemiological studies have shown that the consumption of fruits and vegetables has a beneficial effect on reducing some diseases like cancer and cardiovascular diseases. These benefits have been associated to the presence of antioxidant compounds in those foods, mainly flavonoids. Tomato (Lycopersicum esculentum Mill.) is one of the most worldwide consumed vegetables, in natura or processed. Moreover, tomato is rich in many antioxidant compounds like carotenoids, vitamins and flavonoids. Frequently, thermoprocessed foods are taken as less healthy than in natura foods, mainly because nutrient losses caused by high temperature. So, it is very important to evaluate the effect of processing and storage on tomato antioxidant compounds and on their antioxidant activity. A response surface methodology was used to optimize the phenolics extraction conditions and flavonoids concentration from concentrated tomato paste. The optimized method was validated for total phenolics and total flavonoids spectrophotometric determinations and also for flavonoids quantification by high performance liquid chromatography (HPLC). The spectrophotometric methods were validated for repeatability and recovery. Flavonoids determination by HPLC was validated for selectivity, linearity, precision, recovery and sensibility. Processing and storage effect on tomato antioxidant compounds was evaluated. Total phenolics, total flavonoids, flavonoids by HPLC, ascorbic acid, lycopene and ß-carotene were determined and also the antioxidant activity of hydrophilic and lipophilic fractions were studied using ABTS and DPPH methodologies. It was observed that during processing, in general, there was no loss of the antioxidant compounds present in tomato. During the storage time there was a great loss of ascorbic acid, but all other antioxidant compounds were stable and no changes in their antioxidant activity were observed. The effect of tomato paste processing on the antioxidant activity of phenolic extract was also analyzed through electron-spin resonance spectroscopy (ESR) using Fremy¿s salt, and in a liposome model-system. These and the other antioxidant activity results previously obtained were correlated with the total phenolics content found in the samples in order to better study the antioxidant mechanisms involved. The antioxidant action of tomato samples, collected at different processing steps, was analyzed during 15 days chill storage of high-pressure treated chicken meat balls at 300, 600, and 800 MPa. Addition of 0.30% tomato waste (skin + seeds) or of 0.10% final tomato paste to minced meat led to a lag phase of 6 days for formation of secondary oxidation products in meat treated at 600 MPa. The waste product seemed especially efficient in protecting chicken meat pressurized at 800 MPa, as a notably lower rate of formation of secondary oxidation products was found. This work showed that, although processing and storage of tomato paste might result in loss of the most labile substances like ascorbic acid, the other antioxidant compounds were not affected, and, for some of them, processing increased their availability. Similarly, the antioxidant activities of final products were equal to or greater than the in natura ones and remained unaltered during one year storage. In addition, waste material may have good chances of application as antioxidant in other foods<br>Doutorado<br>Ciência de Alimentos<br>Doutora em Ciência de Alimentos
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Pires, Manoela Alves. "Avaliação da capacidade antioxidante de extratos comerciais de alecrim e chá verde e sua influência na estabilidade de hambúrguer de frango durante armazenamento congelado." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-06102014-110832/.
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A atividade antioxidante de dois extratos comerciais de alecrim e chá verde foi comparada com a atividade do sintético BHA para substituição total do sintético em hambúrguer de frango. A quantificação foi determinada pelos métodos Folin-Ciocalteau, FRAP e DPPH. De acordo com as análises de atividade antioxidante, as dosagens dos extratos naturais foram determinadas, utilizando-se como base o limite de dosagem do BHA (0,01% base gordura) e aplicadas em hambúrgueres de frango: T1: Controle; T2: 0,002% BHA; T3: 0,0038% Chá Verde; T4: 0,001% Chá Verde; T5: 0,048% Alecrim; T6: 0,00186% Alecrim. Foram realizadas análises de composição centesimal e pH e análises de estabilidade no armazenamento congelado: rendimento e redução do diâmetro, índice de TBARs, cor objetiva (parâmetros L*, a* e b*) e teste sensorial de aceitação. No método Folin-Ciocalteau, das análises de atividade antioxidante, o BHA não apresentou diferença com o chá verde (p > 0,05), no método FRAP o melhor (p < 0,05) desempenho foi do BHA e no DPPH o chá verde apresentou maior atividade (p < 0,05). Os resultados de TBARS, nos hambúrgueres, mostraram diferença significativa entre as amostras e também interação amostras x tempo do armazenamento (p < 0,05), sendo que após 120 dias o teste com maior dosagem do extrato de alecrim (T5) não diferiu do sintético (T2) (0,423 e 0,369 índice de TBARs, respectivamente). No aspecto sensorial as amostras não diferiram entre si (p>0,05) nem durante todo o período de armazenamento (p > 0,05). Dentro das condições experimentais pode-se afirmar que o extrato comercial de alecrim pode substituir totalmente o antioxidante BHA em hambúrguer de frango, garantindo a mesma estabilidade oxidativa e sem interferir em sua aceitação sensorial.<br>The antioxidant activity of two commercial extracts, rosemary and green tea, were compared with the activity of the synthetic BHA for total replacement of the synthetic in chicken burger. The spectrometric quantification was determined by UV - VIS methods: Folin - Ciocalteu , FRAP and DPPH . In the Folin-Ciocalteau method the BHA showed no difference with green tea (p > 0.05), in the FRAP method the BHA obtained better (p < 0.05) performance and for DPPH the green tea showed greater activity (p < 0.05). According to the analysis of antioxidant activity, dosages of natural extracts were determined, using as basis the limit dosage of BHA (0.01 % fat base) and applied in chicken burgers: T1: Control, T2: 0.002 % BHA, T3: 0.0038 % Green Tea, T4: 0.001 % Green Tea, T5: 0.048 % Rosemary and T6: 0.00186 % Rosemary. Chemical-physical analysis of chemical composition and pH were made, and also stability analysis: cooking loss and reducing the diameter, TBARs index, objective color (parameters L *, a * and b *) and sensory acceptance test. The results of TBARS showed a significant difference between samples and also samples interaction x storage time (p < 0.05), after 120 days the test with higher dosage of rosemary extract (T5) did not differ from synthetic (T2) (0.423 and 0.369 TBARS index, respectively), thus better performance than the other tests. The sensory evaluation results showed that the samples did not differ during the storage period (p > 0.05). According the experimental conditions can be concluded that the commercial rosemary extract can completely replace the antioxidant BHA.
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Vicente, Silvio José Valadão. "Caracterização antioxidante do café (Coffea arabica, L.) e efeitos da sua administração oral em ratos." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/6/6133/tde-10092009-092017/.
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Introdução: Um dos fatores de risco para doenças crônicas não-transmissíveis é o excesso de espécies reativas causado pelo estresse oxidativo. Ácidos fenólicos atuam na defesa contra estas espécies, agindo como antioxidantes e como fatores de transcrição para as enzimas antioxidantes fase II (superóxido dismutase, catalase e glutationa peroxidase). Vários alimentos possuem ácidos fenólicos na composição porém o café se destaca pelo alto conteúdo dos mesmos e por ser consumido mundialmente. Objetivos: a) Comparar a capacidade antioxidante e a estabilidade dos cafés regular e descafeinado ao longo de seis meses; b) Verificar o tempo de resposta e possíveis correlações dose-resposta do efeito antioxidante em ratos após dose única de café; c) Avaliar o efeito antioxidante e possíveis danos hepáticos em ratos submetidos a doses repetidas de café durante 30 dias. Métodos: na etapa in vitro, foram analisados os compostos fenólicos totais, os principais ácidos fenólicos, a capacidade antioxidante (ORAC e DPPH) e a estabilidade destes parâmetros nos cafés regular e descafeinado durante seis meses. Na etapa in vivo, foram utilizados ratos machos Wistar, sendo dosadas as enzimas fase II e o ORAC, além do exame histopatológico e biomarcadores. Resultados: o café regular apresentou capacidade antioxidante inicial superior ao descafeinado com compostos fenólicos totais iguais e maiores teores de ácido fenólicos (15,3% cafêico, 17,0% p-cumárico e 38,1% ferúlico), ORAC (20,8%) e DPPH (3,9%). Após 6 meses, as amostras fechadas à vácuo praticamente não sofreram perdas, as abertas mantidas a 4oC apresentaram perdas medianas (9,6% fenólicos totais, 4,5-8,2% ácidos fenólicos, 21,3-21,6% ORAC e 2,8-3,2% DPPH) e as mantidas abertas a 20oC exibiram perdas elevadas (14,4-19,8% fenólicos totais, 11,9-19,6% ácidos fenólicos, 38,8-49,9% ORAC e 2,1- 3,8% DPPH). Após dose única de café para os ratos, o tempo de resposta máxima para as enzimas fase II e ORAC foi de 1 hora, com significância estatística para as enzimas (p=0,015 SOD e Cat, p=0,007 GPx e p=0,403 ORAC). Após diferentes doses, foram obtidas correlações dose-resposta positivas e com significância estatística para as enzimas (p=0,050 SOD, p=0,033 Cat, p=0,008 GPx e p=0,113 ORAC). Após doses repetidas (30 dias), a atividade das enzimas antioxidantes e o ORAC apresentaram grandes aumentos (74,8% SOD, 59,4% Cat, 135,2% GPx e 25,1% ORAC), todos estatisticamente significativos (p<0,001 para todos). O tecido hepático e os biomarcadores não apresentaram alterações em relação ao grupo controle. Conclusões: o café regular apresentou capacidade antioxidante superior ao descafeinado, os dois cafés não apresentaram perdas das características antioxidantes após seis meses se mantidos selados à vácuo e a administração oral de café regular aumentou a condição antioxidante dos ratos de maneira significativa, sem causar danos hepáticos.<br>Introduction: A risk factor for several degenerative diseases is the excess of reactive species caused by oxidative stress. Phenolic acids share in the defense against those species, acting as antioxidants and as transcriptional factors for the phase II antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase). Several foods have phenolic acids in their composition but coffee stands out by the high contend of them and to be consumed worldwide. Objectives: a) Compare the antioxidant capacity and the stability of regular and decaffeinated coffees along six months; b) Verify the time of response and possible dose-response correlations of antioxidant effect in rats after a single dose of coffee; c) Evaluate the antioxidant effect and possible hepatic damages in rats submitted to repetitive doses along 30 days. Methods: in the in vitro step, it was analyzed the total phenolic compounds, main phenolic acids, antioxidant capacity (ORAC and DPPH) and the stability of these parameters in regular and decaffeinated coffees along six months. In the in vivo step, it was used male Wistar rats, being analyzed phase II enzymes and ORAC, besides histopathologic examination and biomarkers. Results: regular coffee presented a higher initial antioxidant capacity than decaffeinated coffee with equal total phenolic compounds and higher contend of phenolic acids (15.3% caffeic, 17.0% p-coumaric and 38.1% ferulic), ORAC (20.8%) and DPPH (3.9%). After six months, closed samples kept under vacuum practically did not show any losses, opened samples kept at 4oC presented regular losses (9.6% total phenolic compounds, 4.5-8.2% phenolic acids, 21.3-21.6% ORAC and 2.8-3.2% DPPH) and opened samples kept at 20oC exhibited big losses (14.4-19.8% total phenolic compounds, 11.9-19.6% phenolic acids, 38.8-49.9% ORAC and 2.1-3.8% DPPH). After a single dose of coffee for rats, time for maximum response of phase II enzymes and ORAC was 1 hour, with statistic significance for enzymes (p=0.015 SOD and Cat, p=0.007 GPx and p=0.403 ORAC). After different doses, it was obtained positive dose-response correlations, with statistic significance for enzymes (p=0.050 SOD, p=0.033 Cat, p=0.008 GPx and p=0.113 ORAC). After repetitive doses (30 days), the activity of antioxidant enzymes and ORAC showed big increases (74.8% SOD, 59.4% Cat, 135.2% GPx and 25.1% ORAC), all with statistic significance (p<0.001 for all). Hepatic tissue and biomarkers did not show any change compared to control group. Conclusions: regular coffee presented higher antioxidant capacity than decaffeinated coffee, both coffees did not show any antioxidant losses after six months if kept sealed under vacuum and the oral administration of regular coffee increased significantly the antioxidant condition of rats, without any hepatic damages.
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Scott, Brigitte Clare. "Analysis of the antioxidant action of potential food antioxidants and therapeutic agents." Thesis, King's College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338445.
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Funari, Cristiano Soleo de [UNESP]. "Estudos químicos e biológicos de espécies do gênero Lippia (Verbenaceae) nativas no Cerrado paulista." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/105823.
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funari_cs_dr_araiq.pdf: 2600402 bytes, checksum: 4840dd71ba347ae01113e7c55ed07595 (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)<br>A criação de um modelo nacional de saúde pautado nas aptidões e carências brasileiras é tida como fundamental para tornar o acesso à saúde pública mais abrangente e de melhor qualidade. O histórico do desenvolvimento mundial de medicamentos, a biodiversidade e os conhecimentos tradicionais associados a esta, e as competências científicas existentes no Brasil evidenciam a importância da bioprospecção. O gênero Lippia é amplamente empregado em etnomedicina e é constituído principalmente por espécies aromáticas. As investigações químicas e farmacológicas estão majoritariamente concentradas nos seus óleos essenciais, mas alguns componentes fixos, como flavonóides, fenilpropanóides, naftoquinóides e iridóides glicosilados já foram relatados. O Brasil abriga a maioria das espécies deste gênero, mas diversos problemas taxonômicos dificultam o estabelecimento de dados precisos. O stress oxidativo é apontado como ponto central no desenvolvimento de processos degenerativos associados ao envelhecimento e a diversas doenças. Conseqüentemente, terapias antioxidantes estão sendo propostas para o seu tratamento ou prevenção. Este trabalho descreve o fracionamento de extratos de folhas e de ramos de L. salviaefolia guiado por testes antioxidantes que levou ao isolamento de 16 substâncias fenólicas, sendo 4 isômeros interconversíveis inéditos, 2S e 2R-3',4',5,6-tetraidroxi-7-O-β-glicopiranosil-flavanona (12a e 12b) e 2S e 2R-5,8,3',4'-tetraidroxi-7-O-β-glicopiranosil-flavanona (13a e 13b), que foram identificadas em mistura por estudos extensivos de Ressonância Magnética Nuclear e Espectrometria de Massas. Foram isoladas também 8 substâncias do extrato de raízes de L. lupulina, selecionado com base em estudos iniciais de desreplicação por Cromatografia Líquida de Alta Eficiência acoplada a Arranjo de Fotodiodos (CLAE-DAD). Os extratos...<br>The creation of a national model of health guided by need and capacity in Brazil is seen as fundamental to making access to public health more comprehensive and of better quality. The historical development of world medicine, the biodiversity and traditional knowledge associated with this, and the scientific expertise available in Brazil highlight the significance of bioprospecting in this country. The genus Lippia is widely used in ethnomedicine. Since most of its species are aromatic, the studies on the chemistry and pharmacology of this genus are mainly focused in essential oils, but some fix compounds, such as flavonoids, phenylpropanoids, naphthoquinoids and iridoids glucosides have also been reported. It is estimated that Brazil hosts most of Lippia species, but several taxonomical problems related to this species hamper the establishment of accurate data difficult. Oxidative stress has a central role in the development of degenerative processes associated to aging and several diseases, including cancer and inflammation. Consequently, antioxidant therapies are being proposed for their treatment or prevention. This work describes the fractionation procedures of L. salviaefolia leaves and stems extracts guided by simple antioxidant assays which led to 16 phenolic compounds, including 4 novel interconverting isomers (2S) and (2R)-3',4',5,6-tetrahydroxyflavanone-7-O-β-glucopyranoside (12a and 12b) and (2S) and (2R)-3',4',5,8-tetrahydroxyflavanone-7-O-β-glucopyranoside (13a and 13b), which were identified in mixture by extensive use of 1D and 2D NMR and MS techniques. Additionaly, other 8 compounds were isolated from the extract of roots of L. lupulina, which led to its selection for dereplication studies by High Pressure Liquid Chromatography-Photodiode Array Detector (HPLC-DAD). The bioactivity evaluation of extracts and isolated compounds from L. salviaefolia was initiated... (Complete abstract click electronic access below)
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Giada, Maria de Lourdes Reis. "Avaliação da capacidade antioxidante dos compostos fenólicos do cotilédone da semente de girassol (Helianthus annuus L.) rajada." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/9/9132/tde-22082017-093259/.
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No presente trabalho foi avaliada a capacidade antioxidante in vitro dos extratos do cotilédone da semente de girassol rajada, obtidos por extração seqüencial com solventes de diferentes polaridades, bem como avaliado o potencial antioxidante in vitro do extrato que apresentou maior capacidade in vitro. Todos os parâmetros in vitro (sistema β-caroteno/ácido Iinoléico, métodos FRAP, DPPH, ORAC e Rancimat) indicaram o extrato aquoso (EAq) como o de maior capacidade. Neste extrato, o ácido clorogênico (12,88%) foi identificado como o principal componente dos ácidos fenólicos. Na avaliação da capacidade antioxidante in vitro, ambas as determinações empregadas (TBARS e perfil de ácidos graxos) indicaram o EAq como capaz de exercer um efeito protetor sobre os ácidos graxos poliinsaturados dos tecidos adiposo, cerebral, hepático e plasmático de ratos Wistar machos recém-desmamados.<br>The aims of this work were to evaluate the in vitro antioxidant capacity of listed sunflower cotyledon extracts, obtained by a sequential extraction with solvents of different polarities, and to evaluate the in vitro antioxidant potential of the sample extract with highest in vitro capacity. Ali the in vitro parameters (β-carotene/linoleic acid system, FRAP, OPPH, ORAC and Rancimat methods) indicated the aqueous extract (EAq) as the extract with highest capacity. In this extract, the chlorogenic acid (12.88%) was identified as the principal fraction of phenolic acids. In the in vitro antioxidant capacity evaluation, both determinations used (TBARS and fatty acids profile) gave indication that the EAq was capable to exerce a protective effect on the polyunsaturated fatty acids of the adipose, cerebral, hepatic and plasm tissues of Wistar male rats just-weaned.
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Křenová, Alena. "Antioxidační aktivita vybraných druhů drobného ovoce." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2015. http://www.nusl.cz/ntk/nusl-217149.
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This diploma´s thesis deals with the determination of total antioxidant activity of red and white gooseberries and red, white and black currants. There are available information about small fruits, an overview of natural and synthetic antioxidants and a summary of the methods to determine the total antioxidant activity in the theoretical part. Frozen fruit samples were provided by Research and Breeding Institute of Pomology Holovousy Ltd. in the project QI111A141 – Research of new technologies in the cultivation of gooseberries and currants with a focus on quality and use of fetuses (Ministry of Agriculture). The total antioxidant activity of red and white gooseberries and currants was measured by spectrophotometric methods using free radicals ABTS•+ and DPPH and was expressed as a Trolox equivalent. The total antioxidant activity of black currants was measured by electron paramagnetic resonance using free radicals ABTS•+ and DPPH and expressed as a TEACABTS and a TEACDPPH. There were measured 8 species of red gooseberries, 6 species of white gooseberries, 12 species of red currants, 6 species of white currants and 8 species of black currants in this thesis. The highest values of total antioxidant activity showed species of red and white gooseberries Alan, Karmen, Pax and Invicta and species of red and white currants Rovada, Orion and Olin. Among black currants, species Ometa and Ruben had the highest values of total antioxidant activity.
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Souza, Jane Cristina de 1981. "Atividade antioxidante in vitro e in vivo de suco de uva e da norbixina." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256113.
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Orientador: Debora de Queiroz Tavares<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos<br>Made available in DSpace on 2018-08-10T03:01:19Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008<br>Resumo: Estudos epidemiológicos demonstram que o consumo de dietas ricas em alimentos e bebidas de origem vegetal está associado à redução do desenvolvimento de doenças crônico-degenerativas. Tais alimentos são fontes de substâncias como carotenóides e polifenóis que podem atuar como agentes quimioprotetores, reduzindo os danos causados por espécies reativas de oxigênio, formadas tanto em condições fisiológicas quanto patológicas. Os objetivos do trabalho foram determinar in vivo a atividade antioxidante do suco de uva e da norbixina contra o estresse oxidativo provocado pela administração de Acetaminofeno (AAP), assim como determinar in vitro, a capacidade antioxidante dos sucos durante o processamento e estocagem. Foram dosados os teores de fenólicos totais pelo método de Folin-Ciocalteau, Catequinas e Epicatequinas por CLAE, principais componentes polares ativos por espectrometria de massa com ionização por electrospray com infusão direta (ESI-MS) e capacidade antioxidante pelo método do DPPH. Para determinação da atividade antioxidante in vivo foi conduzido um ensaio biológico com duração de 30 dias. Foram utilizados 30 ratos Wistar machos divididos em 6 grupos (n=5). Os animais ingeriram, duas vezes ao dia, 1 ml de suco de uva Concord (CGJ) (concentração de polifenóis 24mg/mL) ou 1 mL de solução aquosa de Norbixina (Nb) (concentração de 24mg/mL), ou 1 mL de água. Nos 29º e 30º dias os animais receberam intraperitonealmente uma dose de Acetaminofeno (100mg/kg de peso corpóreo). Após o sacrifício foram retirados fígado e rins para análises histológicas e enzimáticas. Os tecidos hepáticos e renais foram analisados por Microscopia Ótica (MO) e Eletrônica de transmissão (MET). Foram dosados os níveis de peroxidação lipídica (TBARS), a atividade das enzimas antioxidantes (SOD, MnSOD, CuZnSOD, GPx, GPx Se-dependente e catalase). Os resultados in vitro mostram que os sucos apresentam altos teores de fenólicos totais e capacidade antioxidante, os quais são mantidos durante o processamento e armazenamento do produto. Os resultados in vivo mostram que no fígado de animais tratados com CGJ+AAP e Nb+AAP houve diminuição significativa (p£0.05) da peroxidação lipídica induzida pelo AAP em 18.7% e 21.0% respectivamente. Por outro lado no rim, a redução foi de 7.1% no grupo CGJ+AAP e 5.3%, no grupo Nb+AAP, valores estes não diferentes (p£0.05) em comparação ao grupo AAP. Os níveis de peroxidação lipídica dos grupos que receberam Suco de uva Concord ou Norbixina, sem a presença de acetaminofeno, não diferiram do grupo Controle (p£0.05). O grupo CGJ+AAP mostrou um aumento significativo de 200% no fígado e de 100% nos rins na atividade de catalase em comparação ao grupo AAP. No grupo Nb+AAP a atividade de catalase aumentou 54% no fígado, enquanto que no rim, não ocorreu aumento na atividade de catalase em comparação ao grupo AAP. O estudo demonstra que os sucos analisados apresentam alta capacidade antioxidante a qual foi mantida durante as etapas de processamento e estocagem. Fígado e rins respondem de maneira distinta na presença de antioxidantes, porém ambos CGJ e Nb atenuam a toxicidade causada pelo AAP<br>Abstract: Epidemiological studies shown that the consumption of diets rich in plant foods and beverages is associated with reduction in the development of chronic-degenerative diseases. These foods are sources of substances such as carotenoids and polyphenols that can act as chemoprotectives agents, reducing the damage caused by reactive oxygen species, formed both in physiological and pathological conditions. The objectives of this study were to determine, in vivo, the antioxidant activity of grape juice and Norbixin against oxidative stress induced by Acetaminophen (AAP) administration, as well as determine, in vitro, the antioxidant capacity of juices during the processes of manufacturing and storage. Were determined the total phenolic contents using the Folin - Ciocalteau method; Catechin and Epicatechins by CLAE, major polar components by direct infusion and electrospray ionization mass spectrometry (ESI-MS) and antioxidant capacity by the DPPH method. To the antioxidant activity determination in vivo, was conducted a biological assay with 30 days of duration. They were used 30 rats male Wistar divided in 6 groups (n = 5). The animals were given twice daily 1 ml of Concord grape juice (CGJ) (polyphenols concentration 24mg/mL) or 1 mL of aqueous solution Norbixin (Nb) (concentration 24mg/ mL), or 1 mL of water. In 29 ° and 30 ° days, the animals received a dose of Acetaminophen (100mg/kg of body weight). After sacrifice, liver and kidneys were removed for histological and enzymatic analysis. The liver and kidney tissues were analyzed by optical microscopy (OM) and transmission electronic microscopy (TEM). Were measured lipid peroxidation levels (TBARS), the antioxidant enzymes activity (SOD, MnSOD, CuZnSOD, GPx, GPx Se-dependent and catalase). The in vitro results show that juices have high total phenolic levels and antioxidant capacity, which are kept for the processing and storage of these products. In vivo results show that liver of animals treated with CGJ+AAP and Nb+AAP was a decrease significant of lipid peroxidation caused by AAP in 18.7% and 20.99% respectively. On the other hand, in the kidney, the decrease was 7.1% in the CGJ+AAP group and 5.3% in the Nb+AAP group, whereas these values were not statistically different (p£0.05) compared to the group AAP. Concord grape juice or Norbixin tested alone did not differ from Control group. The CGJ+AAP group showed a significant increase of 200% in the liver and 100% in the kidneys in the catalase activity when compared to the AAP group. In Nb+AAP group catalase activity in the liver increased 54%, but in the kidney, there was no increase in activity of catalase compared to the group AAP. In this study was verified that juices showed high antioxidant capacity, which is maintained during the stages of processing and storage. Liver and kidneys showed distinct responses in the antioxidants presence, but both CGJ and Nb reduces AAP-toxicity induced<br>Mestrado<br>Nutrição Experimental e Aplicada à Tecnologia de Alimentos<br>Mestre em Alimentos e Nutrição
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Aucoin, Richard R. "Antioxidants and antioxidant enzymes as biochemical defenses against phototoxin ingestion by insect herbivores." Thesis, University of Ottawa (Canada), 1991. http://hdl.handle.net/10393/7679.
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Many secondary plant compounds are capable of photoactivation resulting in the production of toxic species of oxygen. One mechanism of defense for insects feeding on phototoxic plants may be the presence of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPOX), and glutathione reductase (GR). The activities of these enzymes were examined in larvae of three lepidoptera: Ostrinia nubilalis, Manduca sexta, and Anaitis plagiata. Highest levels of antioxidant enzyme activity were found in A. plagiata, a specialist feeder on Hypericum perforatum, which contains high levels of the phototoxin hypericin. Larvae of A. plagiata fed leaf discs treated with hypericin exhibited a short-term, concentration-dependent decline in enzyme activity. Longer term studies with A. plagiata fed either the phototoxic H. perforatum, or the closely related but non phototoxic H. calycinum, resulted in increased CAT and GR activity in larvae fed the phototoxic plant whereas superoxide dismutase activity was not significantly different. These results suggest that CAT and GR may be inducible defenses against phototoxins. Other insect defenses against phototoxins include specific biochemical defenses such as antioxidants. These antioxidant defenses eliminate or quench the deleterious singlet oxygen and free radicals formed by these phototoxins. We examined the role of dietary antioxidants in protecting the phototoxin-sensitive insect herbivore M. sexta. Elevated dietary levels of the lipid-soluble antioxidants beta-carotene and vitamin E resulted in a concentration-dependent reduction in the mortality associated with treatment of larvae with the phototoxic thiophene $\alpha$-T. Elevated levels of dietary ascorbic acid had no effect whereas reduced levels greatly increased the toxicity of $\alpha$-T. Tissue levels of antioxidants were shown to increase substantially in larvae fed antioxidant-supplemented diets. The results suggest that the ability to absorb and utilize plant-derived antioxidants could be an important defense against photo-activated plant secondary compounds and may have allowed some insects to exploit phototoxic plants. The effects of oxidative stress induced by $\alpha$-T at the biochemical level and the protective effect of antioxidants and antioxidant enzymes were also examined. The phototoxin $\alpha$-T strongly induced lipid peroxidation (LPO) in midgut tissues of the phototoxin-sensitive M. sexta in a UV-dependent manner, however this LPO was prevented when the compound was administered to larvae raised on high vitamin E diets. In the absence of UV, $\alpha$-T caused a significant increase in GPOX, GR, and non-GSH-dependent PER activity over 72 h. However in the presence of UV, $\alpha$-T strongly inhibited GPOX and GR and prevented the increase in PER. $\alpha$-T also affected cellular thiol status with approximately a 50% increase in total and GSH content in midgut tissue, although this was not UV-dependent. The effectiveness of antioxidant enzymes and the antioxidant GSH in providing protection against phototoxins were also examined. Neither the SOD inhibitor DEDC nor the CAT inhibitor 3AT affected the acute toxicity of topically applied $\alpha$-T to M. sexta larvae. The GSH-depleting agent BSO also had no effect on acute toxicity. In contrast, GSH depletion strongly enhanced the chronic (72 h) toxicity of $\alpha$-T when the phototoxin was incorporated into diets. GSH depletion also enhanced LPO in midgut tissue of $\alpha$-T-treated larvae. Implications of the results are discussed in terms of the role antioxidants and antioxidant enzymes may have played in the successful adaptation of some insect species to phototoxin-containing plants. The interrelationships of biochemical, physiological, physical, and behavioural mechanisms of defense are considered.
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Arts, Mariken J. T. J. "Assessing antioxidant activity." [Maastricht : Maastricht : Universiteit Maastricht] ; University Library, Universiteit Maastricht [host], 2007. http://arno.unimaas.nl/show.cgi?fid=8676.
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Gonçalves, Any Elisa de Souza Schmidt. "Avaliação da capacidade antioxidante de frutas e polpas de frutas nativas e determinação dos teores de flavonóides e vitamina C." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-28012009-161811/.
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Os alimentos fornecem não somente nutrientes essenciais necessários para a vida, mas também compostos bioativos com propriedades biológicas ditas promotoras da saúde, tais como atividades antioxidante, antiinflamatória e anticarcinogênica de nutrientes como as vitaminas C, A e E, e de compostos fenólicos como os flavonóides. De maneira geral, a capacidade antioxidante de frutos e hortaliças está relacionada aos teores destes compostos, que impedem a ação dos radicais livres e são o foco de interesse deste trabalho. Desta forma, o objetivo deste trabalho foi identificar fontes potenciais de compostos bioativos através da determinação dos teores de flavonóides, ácido elágico, vitamina C, capacidade antioxidante e inibição de α-glicosidase e α-amilase de frutas e polpas de frutas nativas. Foram analisadas 16 frutas e 6 polpas congeladas de frutas nativas, e destas, camu-camu, cupuaçu, coquinho azedo e cagaita mostraram-se excelentes fontes de vitamina C. Camu-camu, cambuci, uxi e tucumã e as polpas de cambuci, cagaita, coquinho azedo e araçá foram as amostras que apresentaram melhor capacidade antioxidante. Os flavonóides de maior incidência entre as amostras foram quercetina e caempferol. O ácido elágico foi detectado apenas em umbu, camu-camu, cagaita, araçá e cambuci e o teor variou de 218 a 512 mg/100 g de amostra seca. Cambuci e cagaita foram as amostras mais eficientes em inibir α-glicosidase e α-amilase. Em suma, este trabalho mostrou que as frutas nativas brasileiras também podem ser consideradas boas fontes de compostos bioativos.<br>Foods provide not only essential nutrients for life, but also bioactive compounds with health-promoting properties such as antioxidant, anti-inflammatory and hypocholesterolemic activities, which have been related with vitamins A, C and E and phenolics compounds such as flavonoids. In general, antioxidant capacity of fruits and vegetables is linked to the amount of these compounds, which are effective against free radicals. Therefore, the aim of this work was to identify potential sources of bioactive compounds through determination of flavonoids, ellagic acid and vitamin C contents, antioxidant capacity and α-lucosidase and α-amylase inhibition by native fruits and commercial frozen pulps. In this study, 16 native fruits and 6 commercial frozen pulps were analyzed, and camu-camu, cupuaçu, coquinho azedo and cagaita showed themselves as excellent vitamin C sources. Camu-camu, cambuci, uxi and tucumã and commercial frozen pulps of cambuci, cagaita, coquinho azedo and araçá were the samples that presented the highest antioxidant capacity. Quercetin and kaempferol derivatives were the main flavonoids present in most of the samples. Ellagic acid was detected only in umbu, camu-camu, cagaita, araçá and cambuci and the content ranged from 218 to 512 mg/100 g (DW). Cambuci and cagaita showed the highest α-glucosidase and α-amylase inhibitory activity. According to our results, native Brazilian fruits can also be considered as good sources of bioactive compounds.
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Funari, Cristiano Soleo de. "Estudos químicos e biológicos de espécies do gênero Lippia (Verbenaceae) nativas no Cerrado paulista /." Araraquara : [s.n.], 2010. http://hdl.handle.net/11449/105823.
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Orientador: Dulce Helena Siqueira Silva<br>Banca: Lourdes Campaner dos Santos<br>Banca: Edilberto Rocha Silveira<br>Banca: Valdir Cechinel Filho<br>Banca: Mary Ann Foglio<br>Resumo: A criação de um modelo nacional de saúde pautado nas aptidões e carências brasileiras é tida como fundamental para tornar o acesso à saúde pública mais abrangente e de melhor qualidade. O histórico do desenvolvimento mundial de medicamentos, a biodiversidade e os conhecimentos tradicionais associados a esta, e as competências científicas existentes no Brasil evidenciam a importância da bioprospecção. O gênero Lippia é amplamente empregado em etnomedicina e é constituído principalmente por espécies aromáticas. As investigações químicas e farmacológicas estão majoritariamente concentradas nos seus óleos essenciais, mas alguns componentes fixos, como flavonóides, fenilpropanóides, naftoquinóides e iridóides glicosilados já foram relatados. O Brasil abriga a maioria das espécies deste gênero, mas diversos problemas taxonômicos dificultam o estabelecimento de dados precisos. O stress oxidativo é apontado como ponto central no desenvolvimento de processos degenerativos associados ao envelhecimento e a diversas doenças. Conseqüentemente, terapias antioxidantes estão sendo propostas para o seu tratamento ou prevenção. Este trabalho descreve o fracionamento de extratos de folhas e de ramos de L. salviaefolia guiado por testes antioxidantes que levou ao isolamento de 16 substâncias fenólicas, sendo 4 isômeros interconversíveis inéditos, 2S e 2R-3',4',5,6-tetraidroxi-7-O-β-glicopiranosil-flavanona (12a e 12b) e 2S e 2R-5,8,3',4'-tetraidroxi-7-O-β-glicopiranosil-flavanona (13a e 13b), que foram identificadas em mistura por estudos extensivos de Ressonância Magnética Nuclear e Espectrometria de Massas. Foram isoladas também 8 substâncias do extrato de raízes de L. lupulina, selecionado com base em estudos iniciais de desreplicação por Cromatografia Líquida de Alta Eficiência acoplada a Arranjo de Fotodiodos (CLAE-DAD). Os extratos... (resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: The creation of a national model of health guided by need and capacity in Brazil is seen as fundamental to making access to public health more comprehensive and of better quality. The historical development of world medicine, the biodiversity and traditional knowledge associated with this, and the scientific expertise available in Brazil highlight the significance of bioprospecting in this country. The genus Lippia is widely used in ethnomedicine. Since most of its species are aromatic, the studies on the chemistry and pharmacology of this genus are mainly focused in essential oils, but some fix compounds, such as flavonoids, phenylpropanoids, naphthoquinoids and iridoids glucosides have also been reported. It is estimated that Brazil hosts most of Lippia species, but several taxonomical problems related to this species hamper the establishment of accurate data difficult. Oxidative stress has a central role in the development of degenerative processes associated to aging and several diseases, including cancer and inflammation. Consequently, antioxidant therapies are being proposed for their treatment or prevention. This work describes the fractionation procedures of L. salviaefolia leaves and stems extracts guided by simple antioxidant assays which led to 16 phenolic compounds, including 4 novel interconverting isomers (2S) and (2R)-3',4',5,6-tetrahydroxyflavanone-7-O-β-glucopyranoside (12a and 12b) and (2S) and (2R)-3',4',5,8-tetrahydroxyflavanone-7-O-β-glucopyranoside (13a and 13b), which were identified in mixture by extensive use of 1D and 2D NMR and MS techniques. Additionaly, other 8 compounds were isolated from the extract of roots of L. lupulina, which led to its selection for dereplication studies by High Pressure Liquid Chromatography-Photodiode Array Detector (HPLC-DAD). The bioactivity evaluation of extracts and isolated compounds from L. salviaefolia was initiated... (Complete abstract click electronic access below)<br>Doutor
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Bandeira, Rafael dos Santos. "Adição de piruvato e coenzima Q10 ao diluente à base de leite desnatado para refrigeração do sêmen equino." Botucatu, 2019. http://hdl.handle.net/11449/182407.
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Orientador: José Antônio Dell'Aqua Júnior<br>Resumo: O espermatozoide exige um fornecimento constante de energia para a manutenção de suas funções celulares e quando desafiado por processos de criopreservação do sêmen, sofrem danos irreversíveis. Para o desenvolvimento de técnicas que visam o aumento da longevidade espermática, é necessário considerar que mesmo em metabolismo basal, o espermatozoide necessita de substratos para garantir sua motilidade e poder fecundante após a ejaculação. Para atender suas demandas energéticas, estudos recomendam o uso de nutrientes exógenos, como o piruvato de sódio e a coenzima Q10 (CoQ10), substratos fundamentais na bioenergética celular. Visto a importância da refrigeração de sêmen em garanhões e o potencial destas substâncias em melhorar os parâmetros seminais atuando como substrato energético e antioxidante, respectivamente, o presente trabalho tem por objetivo abordar aspectos relacionados ao metabolismo espermático, bem como o papel do piruvato e CoQ10 visando minimizar os efeitos deletérios da refrigeração sobre a qualidade do sêmen equino. Foram adicionadas diferentes concentrações de piruvato de sódio e da CoQ10 ao sêmen de garanhões considerados “good coolers” (GC) e “bad coolers” (BC). Primeiramente, foram estabelecidas as concentrações mais eficazes de piruvato e CoQ10 no diluente de refrigeração BotuSêmen® (Botupharma Botucatu/SP Brasil) para preservar os parâmetros espermáticos na refrigeração a 5° C por até 48 horas. Foi utilizado 1 ejaculado de 25 garanhões das raças Quarto de... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: The spermatozoa require a constant supply of energy for the maintenance of their cellular functions and when challenged by processes of cryopreservation of the semen, they suffer irreversible damages. For the development of techniques that aim to increase sperm longevity, it is necessary to consider that even in basal metabolism, the spermatozoa require substrate to ensure their motility and fertilizing power after ejaculation. To attend their energy demands, studies recommend the use of exogenous nutrients, such as sodium pyruvate and coenzyme Q10 (CoQ10), key substrates in cellular bioenergetics. Considering the importance of semen cooling in stallions and the potential of these substances to improve seminal parameters acting as an energetic and antioxidant substrate, this review aims to address aspects related to cooling, as well as the role of sodium pyruvate and CoQ10 in minimizing the effects of cooling on the quality of equine semen. Different concentrations of sodium pyruvate and CoQ10 have been added to semen from good coolers (GC) and bad coolers (BC). First, the most effective concentrations of sodium pyruvate and CoQ10 in the BotuSêmen® extender (Botupharma Botucatu / SP Brazil) were established to preserve the sperm parameters at 5°C for up to 48 hours. Each ejaculate was split into 7 treatments, with sodium pyruvate and CoQ10 being added at concentrations of 1 mmol/l (P1), 2 mmol/l (P2), 3 mmol/l sodium pyruvate (P3), 25 µmol/l (Q25), 50 µmol/l (Q50) and 75 µmol... (Complete abstract click electronic access below)<br>Mestre
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Queiroz, Yara Severino de. "Efeito do processamento do alho (Allium sativum L.) sobre os seus compostos bioativos e potencial antioxidante in vitro e in vivo." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/6/6138/tde-24022011-113506/.
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Introdução: O aumento do consumo de frutas e hortaliças está associado à redução do risco de ocorrência de doenças crônicas não transmissíveis. Este efeito protetor tem sido atribuído particularmente à presença de vários compostos bioativos como compostos fenólicos e organosulfurados, além de fitosteróis presentes no alho que podem contribuir com os efeitos antioxidante e hipolipemiante. Porém, o processamento do alho pode acarretar mudanças na quantidade e na efetividade dos compostos bioativos. Este trabalho teve como objetivo avaliar se a cocção e a fritura do alho reduziram as concentrações de compostos bioativos, o potencial antioxidante in vitro e in vivo em hamsters hipercolesterolemizados. Métodos: In vitro - foram determinados nos alhos cru, frito e cozido: a) composição centesimal (proteínas, lipídios, cinzas, carboidratos, fibra alimentar solúvel e insolúvel); b) perfil de ácidos graxos; c) teor de fenólicos totais; d) teor de quercetina, miricetina e apigenina; e) fitosteróis; f) alicina; g) teor de cobre, zinco e selênio; h) produtos intermediários da reação de Maillard; i) potencial antioxidante utilizando os testes ORAC (Oxygen radical absorbance capacity), Rancimat® e o sistema -caroteno/ácido linoléico. In vivo - hamsters machos foram distribuidos em 5 grupos com 10 animais em cada grupo. 1 - controle; 2 - hipercolesterolêmico; 3- hipercolesterolêmico e alho cru; grupo 4 - hipercolesterolêmico e alho cozido; grupo 5 - hipercolesterolêmico e alho frito. Os animais foram eutanasiados após 4 semanas de estudo para análises do plasma e do tecido hepático. No plasma foi determinado o potencial antioxidante pelo teste ORAC, o perfil lipídico (colesterol total e frações e triacilgliceróis) e verificado a atividade das enzimas aspartato aminotransferase (AST) e alanina aminotransferase (ALT). No tecido hepático foram avaliadas a atividade das enzimas hepáticas (glutationa peroxidase, catalase e superóxido dismutase) e o potencial antioxidante utilizando dois métodos, ORAC e ensaio cometa. Resultados: In vitro - O teor de fibras totais para o alho cru foi de 10,0por cento (71,6por cento é solúvel e 28,4por cento é insolúvel). O alto conteúdo de ácidos graxos trans no alho frito (14,9por cento ) é devido ao processo de fritura com 50por cento de gordura vegetal hidrogenada. A cocção não alterou o teor dos minerais analisados. O teor de compostos fenólicos nas amostras de alho variou de 4,2 a 187,7 mg EAG/100g (base seca), dependendo do solvente (água, água/metanol, etanol ou acetona) e do método de extração utilizados. A fritura diminuiu os teores de quercetina e alicina em torno de 24por cento e 87por cento , respectivamente. Os fitosteróis -sitosterol e campesterol estão presentes em todas as amostras, sendo que o alho frito apresentou os maiores teores destes compostos em relação aos alhos cru e cozido, além de apresentar stigmasterol. A fritura foi o processamento térmico que contribuiu com os maiores valores de produtos intermediários da reação de Maillard. O potencial antioxidante pelo teste ORAC (extratos etanólicos, metanol/água e acetona) reduziu com o processamento do alho, sendo que a redução foi maior para a fritura. A inibição da oxidação lipídica foi melhor nos extratos metanol/água. In vivo - O grupo de animais que recebeu ração hiperlipemiante e alho cru teve menor ganho de peso em relação aos grupos que receberam alho frito ou cozido. Os alhos cru e cozido foram eficazes na redução de lipídios no plasma dos hamsters. O potencial antioxidante, avaliado pelos testes ORAC e ensaio cometa, dos grupos hipercolesterolemizados suplementados com alho cru ou cozido apresentaram valores superiores em relação ao grupo hipercolesterolemizado não suplementado. Houve aumento da atividade das enzimas antioxidantes catalase, glutationa peroxidase e superóxido dismutase para todos os grupos suplementados com alho. Em todos os grupos estudados não ocorreram danos estruturais ou funcionais no tecido hepático. Conclusões: Os resultados corroboram com o esperado e sugerem que os alhos cru e cozido podem ocasionar benefícios à saúde, haja vista que estes produtos possuem compostos bioativos, efeito hipolipemiante e apresentaram alto potencial antioxidante no plasma e no tecido hepático, além do aumento da atividade de enzimas antioxidantes que estão envolvidas em mecanimos de proteção à saúde<br>Introduction: The increased consumption of fruits and vegetables is associated with reduced risks of chronic diseases. This protective effect has been attributed particularly to the presence of several bioactive compounds such as phenolic and organosulfur compounds, likewise phytosterols present in garlic that may contribute to the antioxidant and lipid-lowering effects. However, the processing of garlic can cause changes in the quantity and effectiveness of bioactive compounds. This study aimed to evaluate whether the cooking and frying of garlic reduced the bioactive compounds concentrations, the antioxidant potential in vitro and in vivo in hypercholesterolemic hamsters. Methods: In vitro - were determined in raw garlic, fried and boiling: a) composition (protein, fat, ash, carbohydrates, dietary fiber, soluble and insoluble), b) fatty acid profile, c) total phenolic content, d ) content of quercetin, myricetin and apigenin, e) phytosterols, f) allicin, g) content of copper, zinc and selenium, h) Maillard reaction products, i) antioxidant potential using the ORAC test (Oxygen radical absorbance capacity), Rancimat® and system -caroteno/ácido linoleic. In vivo - male hamsters were divided into five groups with 10 animals each. 1 - control, 2 hypercholesterolemic, 3 - hypercholesterolemic and raw garlic, 4 - hypercholesterolemic and boiling garlic, group 5 - hypercholesterolemic and fried garlic. Samples of blood and liver were collected after a 4-week experimental period. In plasma were determined the antioxidant potential by the ORAC assay, the lipid profile (total cholesterol and fractions and triacylglycerols) and verified the activity of enzymes aspartate aminotransferase (AST) and alanine aminotransferase (ALT). In liver tissue were evaluated the activity of liver enzymes (glutathione peroxidase, catalase and superoxide dismutase) and the antioxidant potential using two methods, ORAC and comet assay. Results: In vitro - The content of dietary fiber for raw garlic was 10.0per cent (71.6per cent is soluble and 28.4per cent is insoluble). The high content of trans fatty acids in fried garlic (14.9per cent ) is due to the frying process with 50per cent hydrogenated vegetable fat. The cooking did not alter the content of the minerals analyzed. The content of phenolic compounds in garlic samples ranged from 4.2 to 187.7 mg EAG/100g (dry matter), depending on the solvent (water, water / methanol, ethanol or acetone) and the extraction method used. Frying decreased the content of quercetin and allicin around 24per cent and 87per cent respectively. The phytosterols -sitosterol and campesterol are present in all samples, and the fried garlic showed the highest levels of these compounds in relation to raw and boiling garlic, besides presenting stigmasterol. Frying was the heat processing that contributed to the higher values of products of the Maillard reaction. The antioxidant potential by the ORAC assay (ethanol extracts, methanol/water and acetone) was reduced with the processing of garlic, and the reduction was greater for frying. The inhibition of lipid oxidation was better in methanol/water extracts. In vivo - The group of animals that received ration hyperlipidemic and raw garlic had less weight gain compared with groups that received garlic fried or boiling. Raw and boiling garlic were effective in reducing lipids in hamsters plasma. The antioxidant potential (measured by the ORAC and comet assay tests) of the groups hypercholesterolemic supplemented with raw or boiling garlic had higher values than the not supplemented group hypercholesterolemic. There was increased activity of antioxidant enzymes catalase, glutathione peroxidase and superoxide dismutase in all groups supplemented with garlic. In all groups there was no structural or functional damage in liver tissue. Conclusions: These results corroborate the expected and suggest that the raw and boiling garlic may lead to health benefits, given that these products have bioactive compounds, hypolipidemic effect and showed a high antioxidant potential in plasma and liver tissue, in addition to increased activity of antioxidant enzymes that are involved in mechanisms of health protection
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Tomková, Martina. "Obsah antioxidačních látek ve vybraných druzích ovocných a bylinných čajů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216228.
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This diploma project deals with antioxidant and antimutagenic properties of selected herbal and fruit teas commonly used in Czech population. Influence of different tea packaging (bag teas and loose leaf teas) on bioactive compound content was compared. Further, effect of long-term storage in common household conditions was studied. Antioxidant properties of teas were characterized using some group parameters - total antioxidant activity ("Randox Total Antioxidant Status Kit"), total phenolics and total flavonoids - as well as some individual representatives of low molecular weight antioxidants. Higher antixidant content was found in herbal teas than in fruit teas. Comparing bag teas with loose leaf teas higher antioxidant activity was shown in loose leaf teas. Individual antioxidants were analyzed using HPLC method with spectrophotometric detection and verified by on-line LC/MS. IN all tea samples catechins - catechin, epicatechin, epicatechin gallate and other flavonoids - rutin, morin, quercetin, kaempferol, myricetin and luteolin were determined. In most of teas high level of catechin and rutin was detected. The highest level of flavonoids was determined in herbal poured teas. Ascorbic acid content was also determined by HPLC method. Higher vitamine C level was found in most of fruit teas and in rose hip tea. Antimutagenicity of tea extracts was tested by in vitro test using Saccharomyces cerevisiae D7 yeast. High antimutagenic activity showed mainly nettle tea, tutsan tea and most of fruit teas. During long-term storage (1 year, 20°C, darkness) a significant decrease of all analyzed antioxidant parameters was followed. Higher lost of antioxidants was found in fruit teas when compared with the herbal ones.
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Kristinová, Věra. "Zhodnocení antioxidačního působení za použití různých analytických metod." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216420.
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Cílem diplomové práce je zhodnotit antioxidační účinky pěti různých sloučenin s potenciálním využitím jako antioxidanty v potravinách (propylgalát, kávová kyselina, ferulová kyselina, p-kumarová kyselina a L(+)-askorbová kyselina), a to prostřednictvím čtyř běžně používaných testů antioxidační kapacity (FC, FRAP, DPPH, ABTS) a v modelovém systému liposomů za použití volného železa (Fe2+, Fe3+) a hovězího hemoglobinu jako prooxidantů se zvláštním zaměřením na různé koncentrace testovaných sloučenin v systému. K nepřetržitému monitorování oxidace lipidů při pH 5,5 a teplotě 30 °C je použita spotřeba kyslíku. Výsledky této práce mají přispět k lepšímu pochopení základních pro- a antioxidačních mechanismů a faktorů ovlivňující oxidaci buněčných membrán, liposomálních roztoků a emulzí typu olej-ve-vodě stabilizovaných fosfolipidy.
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Oliveira, Luciana de Siqueira. "Evaluation of antioxidant metabolism during development of acerola and sapodilla clones." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=7570.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior<br>Fruit ripening is a complex developmental process involving changes in biochemical, physiological and sensorial characteristics as well as in the oxidative metabolism which result in their quality attributes and antioxidant properties This research described the major changes in the antioxidant systems during development of two tropical fruit species Acerola (Malpighia emarginata D.C) and sapodilla (Manilkara zapota L.) fruits were analyzed at different maturity stages for quality parameters post-harvest antioxidant compounds total antioxidant activity (TAA) antioxidant enzymes activity and cell membrane integrity Ripening process promoted improvements in post-harvest quality of tropical fruits studied In acerola the total vitamin C and total soluble phenols (TSP) content reduced during development which resulted in decline of total antioxidant activity (TAA) In spite of the decline in TSP the yellow flavonoid and total anthocyanins content showed an evident increase at ripening which may be associated to fruit coloring and antioxidant nutrition properties While in sapodilla antioxidant compounds contents reduced significantly during the fruit development which contributed to decreased of TAA that resulting mainly from the decline of phenolics contents such as TSP and yellow flavonoids because sapodilla is not a good vitamin C source The activities of oxygen-scavenging enzymes superoxide dismutase (SOD) catalase (CAT) and ascorbate peroxidise (APX) decreased with tropical fruits ripening which contributed to an increased oxidative stress as evidenced by lipid peroxidation therefore necessary to make easy many changes related to aging The development of tropical fruits studied was accompanied by progressive increase in oxidative and peroxidative stress which can contributed to the fruit postharvest quality and nutritional antioxidant potential<br>O amadurecimento de frutos à um processo complexo do desenvolvimento envolvendo inÃmeras mudanÃas nas caracterÃsticas bioquÃmicas, fisiolÃgicas e sensoriais bem como no metabolismo oxidativo determinando seus atributos de qualidade e propriedade antioxidante Desta forma esse trabalho objetivou analisar as principais mudanÃas no sistema antioxidante durante o desenvolvimento de frutos de duas espÃcies tropicais Os frutos de aceroleira (Malpighia emarginata D.C) clones II 47/1 BRS 235 BRS 236 BRS 237 e BRS 238 e de sapotizeiro (Manilkara zapota L.) clones BRS 227 e BRS 228, foram analisados em diferentes estÃdios do desenvolvimento quanto Ãs variÃveis de qualidade pÃs-colheita compostos antioxidantes atividade antioxidante total (AAT) atividade das enzimas antioxidante e grau de peroxidaÃÃo de lipÃdeos. Durante o processo de desenvolvimento das acerolas o conteÃdo de vitamina C e de polifenÃis solÃveis totais (PST) diminuiu resultando em um declÃnio da atividade antioxidante dos frutos Apesar da reduÃÃo dos PST o conteÃdo de flavonÃides amarelos e antocianinas totais mostraram um aumento evidente com o amadurecimento o que pode estar associado à mudanÃa de cor e propriedades antioxidantes nutricionais da acerola Enquanto no sapoti o conteÃdo dos compostos antioxidantes diminuiu significativamente ao longo do desenvolvimento contribuindo para uma reduÃÃo da AAT resultante principalmente do declÃnio do conteÃdo dos fenÃlicos flavonÃides amarelos e polifenÃis totais pois o sapoti nÃo à considerado uma boa fonte de vitamina C A atividade das enzimas antioxidantes dismutase do superÃxido (SOD) catalase (CAT) e peroxidase do ascorbato (APX) diminuiu ao longo do amadurecimento dos frutos tropicais estudados o que contribuiu para um aumento do estresse oxidativo evidenciado pelo aumento da peroxidaÃÃo de lipÃdeos sendo, portanto necessÃrio para facilitar muitas das mudanÃas relacionadas com a maturaÃÃo O amadurecimento das espÃcies tropicais estudadas foi acompanhado por um aumento do estresse oxidativo e peroxidativo o qual pode contribuir para as alteraÃÃes observadas na qualidade pÃs-colheita dos frutos e para um declÃnio em seu potencial antioxidante
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Noroozi, Mostafa. "Antioxidant effects of flavonoids." Thesis, University of Glasgow, 1998. http://theses.gla.ac.uk/5901/.
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Flavonoids are polyphenolic compounds whose main dietary source are fruits and vegetables. Epidemiological evidence has suggested that dietary flavonoids may protect against heart disease but biological effects have not hitherto been demonstrated directly in humans and there was no consistent evidence about the absorption of flavonoids. The studies performed for this thesis aimed to test antioxidant properties of flavonoids using an in vitro system, ex vivo tests on human tissue (lymphocytes) and in a dietary intervention. The main conclusions of this thesis are: 1. There is a potent antioxidant action of dietary flavonoids demonstrated by the comet assay, of potential importance in protection against cardiovascular disease and cancer. 2. The antioxidant capacities of most major dietary flavonoids are greater than vitamin C. 3. Results from the comet assay and TEAC show reasonable agreement in ranking. 4. Antioxidant activities of free flavonoids are more than the conjugated flavonoids. 5. There was a strong positive correlation between the number of hydroxyl groups of flavonoids and the antioxidant activity. 6. Dietary flavonoids are absorbed and the fasting plasma concentration can be increased 12 fold by a simple and palatable food supplement. 7. Supplementation with onions, tomato ketchup and tea led to protection of lymphocytes against free radical damage (H2O2), a biological effect of potential medical importance possibly attributable to the absorption of dietary flavonoids. 8. Dietary flavonoids intake (and specifically quercetin) can be estimated with reasonable accuracy from 24 hour urinary flavonoid excretion or fasting plasma concentration. 9. The range of dietary flavonoid consumption in ten NIDDM patients was estimated at 20-80 mg/day from their normal diets. On the basis of results in this thesis, dietary difference within this range would influence tissue antioxidant status.
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Jumuddin, Farra Aidah. "Antioxidant properties of NQO2." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/antioxidant-properties-of-nqo2(f92af4c1-401b-4af2-91b5-1b17846023dc).html.
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Dihydronicotinamide riboside (NRH) quinone oxidoreductase 2 (NQO2) is involved in quinone metabolism reducing quinone to hydroquinone. Quinones are products of oestrogen metabolism and are responsible for the oestrogen-initiated breast carcinogenesis. It has been demonstrated that oestrogen quinones are endogenous biological substrates of NQO2 which acting as a detoxification enzyme catalyses the reduction of oestrogen quinones to hydroquinone. Hydroquinone can then be removed by conjugation to glutathione or glucuronic acid. In this study, the oestrogen dependent and oestrogen independent effects of NQO2 in a variety of networks implicated in breast tumorigenesis were investigated aiming to understand the potential role of NQO2 overexpression in mammary carcinomas. The use of NRH as a cofactor for NQO2 is being studied in parallel with the Î2-oestradiol and tamoxifen treatments. The MCF-7, T47D, MDA-MB-231 and MDA-MB-468 breast cancer cells were transfected with increasing amounts of NQO2 and its biological activity in regulating ERα transcriptional activity, reactive oxygen species (ROS) generation, cell cycle control, mitochondrial membrane potential and antioxidant activities including catalase activity, glutathione (GSH) levels and glutathione peroxidase (GPx) activity were studied. NQO2 overexpression in MDA-MB-231 and T47D cells reduced ROS generation. Increasing amounts of transfected NQO2 induced the ERα transcriptional activity in Î2-oestradiol treated MCF-7 and T47D cells and decreased cyclin D1 protein levels in these cells treated with Î2-oestradiol compared to untransfected cells. Reduction of catalase activity was detected in tamoxifen treated T47D cells overexpressing NQO2, an effect that was not evident in Î2-oestradiol treated cells, whereas NQO2 mediated reduction of GSH levels was detected in these cells treated with Î2-oestradiol but not with tamoxifen. Finally, NQO2 affected mitochondrial membrane depolarization in Î2-oestradiol treated MDA-MB-231 cells. Given the fact that NRH is not physiologically synthesized in humans, the results presented in this study are valuable from the fundamental science point of view indicating the existence of a potential link between NQO2 and estrogens affecting a number of biological pathways important for breast carcinogenesis and as such from the clinical angle it could be assumed that NQO2 effects could impact the design of personalised breast cancer treatment of oestrogen receptor positive and negative breast cancers.
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Howe, Kimberly Palazzo. "Mechanical Ventilation Antioxidant Trial." Case Western Reserve University School of Graduate Studies / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=case1112877564.
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Farnese, Fernanda dos Santos. "Efeito do óxido nítrico na atenuação do estresse desencadeado por arsênio em Pistia stratiotes L. (Araceae)." Universidade Federal de Viçosa, 2011. http://locus.ufv.br/handle/123456789/4330.
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Previous issue date: 2011-02-18<br>Fundação de Amparo a Pesquisa do Estado de Minas Gerais<br>Nitric oxide effect on attenuating the stress triggered by arsenic (As) was evaluated in Pistia stratiotes, being the nitric oxide supplied in the form of sodium nitroprusiate (SNP). The plants were cultivated in nutrient solution, pH 6.5, ½ ion force and exposed to four treatments: control (nutrient solution) SNP (0.1 mg L-1); As (1.5 mg L-1); As + SNP (1.5 and 0.1 mg L-1, respectively). The plants remained in this condition for seven days to the analysis of growth and, As and mineral nutrients uptake and for 24 hours, to the analysis of metabolic changes. The As
uptake kinetic was analyzed using six concentrations of this pollutant, in which the plants remained for two hours: 0.0, 0.25, 0.5, 0.75, 1.0 and 1.5 mg L-1. The parameters of As uptake kinetic in P. stratiotes indicate that this metalloid uptake occurs by the high affinity transporters. The absorbed As was accumulated in the vegetal tissues, mainly in the roots, which gave to P.
stratiotes a low translocation factor and a status of probably hyperaccumulator, a characteristic that was not affected by SNP presence. The As accumulation triggered many damages, as the increment of reactive oxygen species (superoxide anion and hydrogen peroxide) and lipid
peroxidation. These damages were reversed by SNP, which apparently acted directly as antioxidant and as a signalizing molecule, stimulating enzymatic (catalase, peroxidase and ascorbate peroxidase) and non-enzymatic (stimulating the ascorbato-glutathione cycle)
antioxidant responses, which reflected in an increase in total antioxidant capacity. As a consequence, As tolerance index increased in the presence of SNP. The photosynthetic
parameters were also affected, with the reduction in the chloroplastic pigments concentration in presence of As, except carotenoids that showed an increase in their concentration. The SNP presence restored pigments concentrantion to the normal levels. The maximum photochemical efficiency of PSII and the quantum yield of electron transport were also negatively affected by As, while the non-photechemical quenching (NPQ) presented significant increment. Carbon assimilation (A) decreased significantly in As presence whereas gs did not alter and the Ci/Ca rate increased, indicating biochemical limitations. The ΦFSII/ ΦCO2 rate was higher in plants
exposed to As. For the mineral nutrients concentration, As exposition decreased iron, magnesium, manganese and phosphorus concentration, but did not alter calcium concentration. Of these nutrients, only phosphorus concentration did not show similar values than control when
As was supplied in combination to SNP. Therefore, nitric oxide, supplied in the form of SNP, was efficient on attenuating damages triggered by As, acting as a direct antioxidant and as a signalizing molecule.<br>O efeito do óxido nítrico na atenuação do estresse desencadeado pelo arsênio (As) foi avaliado em Pistia stratiotes, sendo o óxido nítrico suprido na forma de nitroprussiato sódico (SNP). As plantas, cultivadas em solução nutritiva, pH 6,5, ½ da força iônica, foram expostas a
quatro tratamentos: controle (apenas solução nutritiva); SNP (0,1 mg L-1); As (1,5 mg L-1); As + SNP (1,5 e 0,1 mg L-1, respectivamente). As plantas permaneceram nessas condições por sete dias, para análises de crescimento e absorção de As e nutrientes minerais, e por 24 horas, para
análises de alterações metabólicas. A cinética de absorção de As foi analisada, utilizando-se para isso seis concentrações do poluente, nas quais as plantas permaneceram por duas horas: 0,0; 0,25; 0,5; 0,75; 1,0 e 1,5 mg L-1. Os parâmetros de cinética de absorção de As por P. stratiotes indicam que a absorção do metalóide ocorre por transportadores de alta afinidade. O As absorvido foi acumulado nos tecidos vegetais, principalmente na raiz, conferindo a P. stratiotes baixo fator de translocação e o status de possível hiperacumuladora, características que não foram afetadas pela presença de SNP. O acúmulo de As desencadeou uma série de danos, como
aumento na produção de espécies reativas de oxigênio (ânion superóxido e peróxido de hidrogênio) e na peroxidação lipídica. Estes danos foram revertidos pelo SNP, que aparentemente atuou diretamente como antioxidante e como molécula sinalizadora, estimulando respostas antioxidantes enzimáticas (catalase, peroxidase e peroxidase do ascorbato) e não
enzimáticas (estímulo do ciclo ascorbato-glutationa), o que se refletiu em aumentos na capacidade antioxidante total. Como consequência, o índice de tolerância ao As aumentou na
presença de SNP. Os parâmetros fotossintéticos também foram afetados pela presença de As, sendo que os teores de pigmentos cloroplastídicos diminuíram, com exceção dos carotenóides, que apresentaram aumentos em suas concentrações. A presença de SNP restaurou os teores dos
pigmentos à níveis normais. A eficiência fotoquímica máxima do FSII e o rendimento quântico do transporte de elétrons também foram afetados negativamente pelo As, enquanto coeficiente de extinção não fotoquímica apresentou incrementos significativos. A assimilação líquida de carbono decresceu significativamente na presença de As, enquanto gs não se alterou e a razão Ci/Ca aumentou, indicando a ocorrência de limitações bioquímicas. A razão ΦFSII/ ΦCO2 foi maior nas plantas expostas ao As. O SNP teve efeito protetor tanto sobre a fluorescência quanto sobre as trocas gasosas, restaurando estes parâmetros à níveis normais. Em relação aos teores de nutrientes minerais, a exposição ao As diminuiu os teores de ferro, magnésio, manganês e fósforo, não tendo afetado os teores de cálcio. Destes nutrientes, apenas os teores de fósforo não retornaram a valores semelhantes ao controle quando o As foi suprido em combinação com SNP.
Desta forma o óxido nítrico, suprido na forma de SNP, foi eficaz na atenuação dos danos desencadeados pelo As, agindo tanto como antioxidante direto quanto como molécula
sinalizadora.
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Aragão, Anaiza Bittencourt de [UNESP]. "Caracterização bioquímica e centesimal das espécies Astrocaryum vulgare Mart. (tucumã) e Endopleura uchi (Huber) Cuatrec. (uxi) nativas da região Amazônica." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/88016.
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000723046.pdf: 1189275 bytes, checksum: 2f2ba5841f03b8d01bf227d4b2d9587b (MD5)<br>As espécies Astrocaryum vulgare Mart. e Endopleura uchi (Huber) Cuatrec., popularmente conhecidas como tucumã e uxi, respectivamente, são frutos nativo da região amazônica com propriedades físico-químicas, centesimal e organolépticas de grande valor para a indústria alimentícia, cosmética e farmacêutica. O tucumã é um fruto rico em compostos de pró-vitamina A, vitamina E, ácidos graxos saturados e poliinsaturados, carboidratos e fibras. O uxi também é uma fonte de ácidos graxos, fibras, esteróides, sais minerais e vitaminas C e E, ainda pouco estudado pela comunidade científica. O valor nutricional é um dos principais fatores que conduzem ao crescente interesse pelo consumo de frutas no país, embora muitas frutas nativas da região amazônica, de menor consumo nacional, ainda não tenham sido devidamente pesquisadas quanto a suas propriedades e atividades benéficas à saúde. Essas frutas possuem diferentes compostos bioativos e em decorrência disto, o objetivo deste trabalho é avaliar a composição centesimal e os teores de compostos bioativos, mais especificamente o teor de fenóis, flavonoides, vitamina C e proteínas, bem como, a determinação do potencial antioxidante do tucumã e uxi nativos da Amazônia oriental. Os resultados encontrados nesta investigação indicam que os frutos de tucumã e uxi, respectivamente, apresentam importantes propriedades nutricionais e compostos bioativos como: carboidratos (26,52%; 35,20%), carotenoides (11,7; 7,87 mgEβC.100g-1), fibras (9,0%; 18,05%), lipídeos (22,94%; 13,19%) minerais em especial o cálcio (110,0 mg.100g-1), fenóis (59,6; 51,2 mgEAG.100g-1) e flavonoides (360,36; 555,65 mgEQ.100g-1), além disso, o tucumã apresentou potencial antioxidante com duas espécies reativas de oxigênio distintas, com o radical DPPH (2,06 IC50 mg.mL-1) e HOCl (1,96 IC50 mg.mL-1)...<br>The species Astrocaryum vulgare Mart . and Endopleura uchi ( Huber ) Cuatrec., popularly known as tucumã and uxi respectively, are fruits native to the Amazon region with physic-chemical and organoleptic proximate great value for the food industry , cosmetics and pharmaceuticals. The tucumã is a fruit rich in compounds of pro-vitamin A, vitamin E, polyunsaturated and saturated fatty acids, carbohydrates and fiber. The uxi is also a source of fatty acids, fiber, sterols, minerals, and vitamins C and E, yet little studied by the scientific community. The nutritional value is one of the main factors leading to the growing interest in the consumption of fruits in the country, although many native fruits of the Amazon region, lower domestic consumption, have not been properly screened for their properties and activities beneficial to health. These fruits have different bioactive compounds and due to this, the aim of this study is to evaluate the composition and levels of bioactive compounds, specifically the phenols, flavonoids, vitamin C and protein, as well as the determination of the antioxidant potential of tucumã and uxi natives of the eastern Amazon. The results in this research indicate that fruits tucumã and uxi, respectively, have important nutritional properties and bioactive compounds such as: carbohydrates (26,52%; 35,20%), carotenoids (11,7; 7,87 mgEβC.100g-1), fibers (9,0%, 18,05%) , lipids (22,94%; 13,19%), especially minerals calcium (110,0 mg 100g-1), phenol (59,6; 51,2 mgEAG.100g-1) and flavonoids (360,36; 555,65 mgEQ.100g-1), moreover, the antioxidant tucumã presented with two different reactive oxygen species, with DPPH (2,06 IC50 mg.mL-1) and HOCl (1,96 IC50 mg.mL -1). In summary, the result of the study in this work allows the appreciation of the fruits as functional food nationally and offers an alternative... (Resumo completo, clicar acesso eletrônico abaixo)
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Aragão, Anaiza Bittencourt de. "Caracterização bioquímica e centesimal das espécies Astrocaryum vulgare Mart. (tucumã) e Endopleura uchi (Huber) Cuatrec. (uxi) nativas da região Amazônica /." Araraquara, 2013. http://hdl.handle.net/11449/88016.
Full textAbstract:
Orientador: Olga Maria Mascarenhas de Faria Oliveira<br>Banca: Celia Maria de Sylos<br>Banca: Mariza Pires de Melo<br>Resumo: As espécies Astrocaryum vulgare Mart. e Endopleura uchi (Huber) Cuatrec., popularmente conhecidas como tucumã e uxi, respectivamente, são frutos nativo da região amazônica com propriedades físico-químicas, centesimal e organolépticas de grande valor para a indústria alimentícia, cosmética e farmacêutica. O tucumã é um fruto rico em compostos de pró-vitamina A, vitamina E, ácidos graxos saturados e poliinsaturados, carboidratos e fibras. O uxi também é uma fonte de ácidos graxos, fibras, esteróides, sais minerais e vitaminas C e E, ainda pouco estudado pela comunidade científica. O valor nutricional é um dos principais fatores que conduzem ao crescente interesse pelo consumo de frutas no país, embora muitas frutas nativas da região amazônica, de menor consumo nacional, ainda não tenham sido devidamente pesquisadas quanto a suas propriedades e atividades benéficas à saúde. Essas frutas possuem diferentes compostos bioativos e em decorrência disto, o objetivo deste trabalho é avaliar a composição centesimal e os teores de compostos bioativos, mais especificamente o teor de fenóis, flavonoides, vitamina C e proteínas, bem como, a determinação do potencial antioxidante do tucumã e uxi nativos da Amazônia oriental. Os resultados encontrados nesta investigação indicam que os frutos de tucumã e uxi, respectivamente, apresentam importantes propriedades nutricionais e compostos bioativos como: carboidratos (26,52%; 35,20%), carotenoides (11,7; 7,87 mgEβC.100g-1), fibras (9,0%; 18,05%), lipídeos (22,94%; 13,19%) minerais em especial o cálcio (110,0 mg.100g-1), fenóis (59,6; 51,2 mgEAG.100g-1) e flavonoides (360,36; 555,65 mgEQ.100g-1), além disso, o tucumã apresentou potencial antioxidante com duas espécies reativas de oxigênio distintas, com o radical DPPH (2,06 IC50 mg.mL-1) e HOCl (1,96 IC50 mg.mL-1)... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: The species Astrocaryum vulgare Mart . and Endopleura uchi ( Huber ) Cuatrec., popularly known as tucumã and uxi respectively, are fruits native to the Amazon region with physic-chemical and organoleptic proximate great value for the food industry, cosmetics and pharmaceuticals. The tucumã is a fruit rich in compounds of pro-vitamin A, vitamin E, polyunsaturated and saturated fatty acids, carbohydrates and fiber. The uxi is also a source of fatty acids, fiber, sterols, minerals, and vitamins C and E, yet little studied by the scientific community. The nutritional value is one of the main factors leading to the growing interest in the consumption of fruits in the country, although many native fruits of the Amazon region, lower domestic consumption, have not been properly screened for their properties and activities beneficial to health. These fruits have different bioactive compounds and due to this, the aim of this study is to evaluate the composition and levels of bioactive compounds, specifically the phenols, flavonoids, vitamin C and protein, as well as the determination of the antioxidant potential of tucumã and uxi natives of the eastern Amazon. The results in this research indicate that fruits tucumã and uxi, respectively, have important nutritional properties and bioactive compounds such as: carbohydrates (26,52%; 35,20%), carotenoids (11,7; 7,87 mgEβC.100g-1), fibers (9,0%, 18,05%), lipids (22,94%; 13,19%), especially minerals calcium (110,0 mg 100g-1), phenol (59,6; 51,2 mgEAG.100g-1) and flavonoids (360,36; 555,65 mgEQ.100g-1), moreover, the antioxidant tucumã presented with two different reactive oxygen species, with DPPH (2,06 IC50 mg.mL-1) and HOCl (1,96 IC50 mg.mL -1). In summary, the result of the study in this work allows the appreciation of the fruits as functional food nationally and offers an alternative... (Resumo completo, clicar acesso eletrônico abaixo)<br>Mestre
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Gomes, Bárbara Bicalho. "Biodisponibilidade da clorofilina cúprica e seu impacto sobre o estresse oxidativo e parâmetros nutricionais em estudo com ratos." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/9/9132/tde-21072016-123319/.
Full textAbstract:
A ingestão de clorofilina cupnca (Chl-Cu), na forma de corante ou suplemento alimentar tem sido associada a potenciais efeitos benéficos e à prevenção de doenças crônicas. Contudo, são poucos os estudos relativos à sua absorção in vivo, atividade antioxidante e impacto no estado nutricional. Diante desses fatos, foram realizados três experimentos com ratos, nos quais foram fornecidas dietas suplementadas com o 1 e 3% de Chl-Cu. No primeiro experimento foi comprovada a absorção da Chl-Cu para o sangue e distribuição para fígado e rins. A análise da Chl-Cu comercial por CLAE evidenciou a presença de dois componentes principais, a clorina cúprica e4 e clorina cúprica e6. A clorina cúprica e4 foi efetivamente absorvida e detectada no soro, fígado e rins, enquanto a clorina cúprica e6 não foi detectada. Esses resultados indicam que a clorina cúprica e6 foi degradada durante a passagem pelo trato gastrointestinal ou não foi absorvida e distribuída para os órgãos. A análise histológica do intestino não indicou qualquer alteração morfológica. No segundo experimento foi avaliado o potencial antioxidante da Chl-Cu em ratos sob estresse oxidativo induzido por deficiência de vitamina E, e administração concomitante de Chl-Cu na dieta. A Chl-Cu foi capaz de proteger o tecido cerebral contra o aumento nos níveis de TBARS, mas o mesmo não foi observado no tecido hepático. Não houve diferença significativa na atividade das enzimas antioxidantes (CAT, SOD, GPx e GR) entre os grupos controle, deficiente em vitamina E e suplementado com Chl-Cu. Desta forma, o efeito antioxidante da Chl-Cu parece ser relacionado a uma proteção contra a peroxidaçãolipídica in situ, mas não com a modulação enzimática. Foi possível observar ainda, que os animais que receberam suplementação com Chl-Cu apresentaram ganho de peso menor que os respectivos controles. Um terceiro experimento foi realizado para investigar se o reduzido ganho de peso dos animais foi causado pela baixa aceitação da dieta ou estaria relacionado a algum efeito antinutricional da Chl-Cu. Em ensaio biológico pair-fed, o efeito negativo da Chl-Cu no desenvolvimento dos animais foi confirmado. A ingestão do pigmento levou também a uma diminuição na digestibilidade protéica aparente indicando ter havido comprometimento na absorção do N protéico e possivelmente de algum outro nutriente..A literatura indica a formação de complexos da Chl-Cu com diferentes componentes alimentares apoiando a hipótese de que a Chl-Cu possa ter interferido na utilização de proteínas e possivelmente de outros nutrientes pelo organismo animal.<br>The ingestion copper chlorophyllin (Cu-Chl) in form of as food colorant or supplement has been associated with potential beneficiai effects and the prevention of chronic diseases. However, little is known about Cu-Chl absorption in vivo, its antioxidant activity and its impact on status nutritional. In view of these facts, three experiments were carried out on rats fed 1 and 3% Cu-Chl supplemented diets. In the first experiment, the absorption of the pigment into the bloodstream and distribution to the liver and kidneys was comproved. HPLC analysis of food-grade Cu-Chl evidenced two main components, copper-chlorin e6 and copper-chlorin e4. The Cu-chlorin e4 was effectively absorbed and found in serum, liver and kidneys, while Cu-chlorin e6 was not detected. This result indicates that Cu-chlorin e6 was either not absorbed and distributed to organs or was degraded during its passage through the gastrointestinal tract. Histological analyses of the intestine did not show any morphological alteration. In a second experiment the antioxidant potential of Cu-Chl in rats under oxidative stress induced by vitamin E deficiency and simultaneous Cu-Chl administration in diet was investigated. The presence of chlorophyllin protected brain tissue from increased TBARS leveis, however the same effect was not observed in liver. There was no significant differences in activities of antioxidant enzymes (CAT, SOD, GPX and GR) among control, vitamin E deficient and Cu-Chl-supplemented groups. Therefore, any antioxidant effect of Cu-Chl seems to be related to in situ protection against peroxidation but not to antioxidant enzyme modulation. Weight gains of the animais receiving Cu-Chl supplemented diets were lower than those of the control group. A third experiment was conducted to evaluate whether the reduced weight gain was caused by low food acceptance or by an antinutritional effect of Cu-Chl. This biological pair-fed test confirmed the negative effect of CuChl on the development of rats. The pigment ingestion also decreased the apparent protein digestibility indicating that N protein and possibly other nutrients had itsabsorption compromised. Literature evidenced formation of Cu-Chl complexes with different food components supporting the hypothesis that Cu-Chl might have interfered in the utilization of proteins and possibly other nutrients by the animal organism.
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Adelakun, Oluyemisi Elizabeth. "Biocatalytic production of new antioxidant compounds and the characterization of their antioxidant effects." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/1528.
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Thesis (DTech(Biomedical Technology ))-- Cape Peninsula University of Technology, 2012<br>Antioxidants are an important class of compounds that quench reactive free radical intermediates formed during oxidative reactions. They prevent oxidative reactions in food and protect biological tissues against oxidative damage. Plant phenols and phenolic acids are increasingly becoming a subject of intensive research due to their bioactive properties such as antioxidant, anti-mutagenic, anti-viral and anti-inflammatory activity. Modification of the structure of natural phenolic compounds can be achieved through the use of enzymes in biocatalysis reactions with the potential to enhance the antioxidant capacity of these natural phenolic compounds. The work reported here employed the oxidative enzyme, laccase from Trametes pubescens, in the modification of the antioxidant phenolic molecules, ferulic acid and 2,6-dimethoxyphenol (2,6-DMP) as a way of enhancing their antioxidant capacity. In addition, various phenolic compounds were focused upon for coupling reactions, with the aim to increase the antioxidant capacity of the compounds. The T. pubescens strain was cultured in a 4L airlift reactor and extracellular laccase production was monitored using the standard ABTS assay. The enzyme was isolated and purified from the culture filtrate once optimal enzyme production was detected. The enzyme was purified using standard ammonium sulphate precipitation and dialysis.
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Horsley, Elizabeth Teresa May. "Mechanism of the antioxidant to prooxidant switch for dietary antioxidants when LDL becomes partially oxidised." Thesis, University of Reading, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250673.
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Souza, Josà Roberto Rodrigues de. "Sistemas de liberaÃÃo controlada de nutracÃuticos- liberaÃÃo in vitro de magiferina a partir de microesferas de pectina/quitosana." Universidade Federal do CearÃ, 2009. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=4652.
Full textAbstract:
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico<br>A incorporaÃÃo de compostos nutracÃuticos como vitaminas, probiÃticos, peptÃdeos bioativos e antioxidantes em sistemas alimentÃcios proporciona uma maneira simples de desenvolver novos alimentos funcionais que podem ter benefÃcios fisiolÃgicos ou reduzir os riscos de doenÃas. Pectinas tÃm sido investigadas por sua capacidade de produzir esferas de gÃis de pectinato de cÃlcio contendo bioativos. Quitosana tambÃm tem sido muito utilizada na preparaÃÃo de esferas por suas propriedades mucoadesivas. Neste estudo, trÃs tipos de esferas de pectina/cÃlcio/quitosana com diferentes graus de reacetilaÃÃo foram produzidas no intuito de encapsular um potente antioxidante natural extraÃdo da manga, a mangiferina. Inicialmente, duas amostras de pectina cÃtrica foram caracterizadas por FTIR, 1H RMN, Reologia e GPC. A pectina cÃtrica com menor grau de metoxilaÃÃo foi escolhida para a preparaÃÃo das esferas por apresentar melhores propriedades geleificantes. As esferas produzidas foram caracterizadas por FTIR, MEV e intumescimento. A formaÃÃo do complexo pectina/cÃlcio/quitosana reacetilada foi observada por FTIR e MEV. Foi realizado um estudo de liberaÃÃo controlada de mangiferina a partir de trÃs tipos de esferas obtidas por duas metodologias diferentes. Os valores de percentual de liberaÃÃo foram bastante significativos, chegando atà 75%. O comportamento dos mecanismos de liberaÃÃo de mangiferina das esferas de pectina/cÃlcio/quitosana mostrou que o bioativo foi liberado a partir da matriz principalmente por meio de relaxaÃÃo das cadeias polimÃricas.<br>Incorporation of nutraceuticals compounds such as vitamins, probiotics, bioactive peptides and antioxidants in food systems provides a simple way to develop new functional foods that can have physiological benefits or reduce risks of disease. Pectins have been investigated for their ability to produce spheres of calcium pectinate gels containing bioactive. Chitosan has also been widely used in the preparation of beads due to its mucoadhesive properties. In this study, three types of spheres of pectin/calcium/chitosan with different degrees of reacetylation were produced in order to encapsulate a powerful natural antioxidant extracted from mango, mangiferin. Initially, two samples of citrus pectin were characterized by FTIR, 1H NMR, Rheology and GPC. The citrus pectin with the lowest degree of methoxylation was chosen for the preparation of beads due to its better gelling properties. The beads produced were characterized by FTIR, SEM and swelling. The formation of the reacetylated complex pectin/calcium/chitosan was observed by FTIR and SEM. A study of controlled release of mangiferin was conducted from three types of beads obtained by two different methodologies. The values of percentage of release were quite significant, reaching up to 75%. The mechanisms behaviour for the release of mangiferin from spheres of pectin/calcium/chitosan showed that the bioactive was released from the matrix mainly through relaxation of the polymer chains.
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Santos, Rebeca Cruz dos. "Anacardato de cÃlcio como fonte de Ãcido anacÃrdico na alimentaÃÃo de codornas japonesas em postura." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13246.
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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior<br>Objetivou-se avaliar os efeitos da adiÃÃo do anacardato de cÃlcio como fonte de Ãcido anacÃrdico na raÃÃo de codornas japonesas em postura quanto ao desempenho e parÃmetros de qualidade dos ovos. Foram utilizadas 252 codornas japonesas em fase de postura com 22 semanas de idade, distribuÃdas em delineamento inteiramente casualizado com seis tratamentos e seis repetiÃÃes de sete aves. Os tratamentos aplicados foram: T1 - raÃÃo sem promotor de crescimento (PC); T2 - raÃÃo com promotor de crescimento; T3, T4, T5 e T6 - raÃÃes sem promotor de crescimento e adiÃÃo de 0,25; 0,50; 0,75 e 1,0% de anacardato de cÃlcio (AC), respectivamente. Os tratamentos nÃo influenciaram o consumo de raÃÃo, percentagem de postura, peso do ovo, massa de ovo, conversÃo alimentar e a qualidade dos ovos: percentagem de gema, albÃmen e casca, unidade Haugh, densidade especÃfica, espessura da casca e cor da gema. O anacardato de cÃlcio como fonte de Ãcido anacÃrdico, quando adicionado atà 1% na raÃÃo nÃo influencia o desempenho e qualidade dos ovos de codornas japonesas.<br>The aim of the study was to evaluate the effects of adding calcium anacardate as source of anacardic acid in Japanese laying quails diets on performance and egg quality parameters. A total of 252 Japanese laying quails with 22 weeks of age were used, distributed in completely randomized design, with six treatments and six replications of seven broilers each. The treatments used were: T1 - diet without growth promoter (PC); T2 - diet with growth promoter; T3, T4, T5 and T6 - diets without growth promoter and addition of 0,25; 0,50; 0,75 and 1,0% of calcium anacardate (AC), respectively. The treatments did not affect feed intake, laying percentage, egg weight, egg mass, feed conversion and quality of the eggs: yolk, albumen and shell percentage, Haugh unit, specific gravity, shell thickness and yolk color. The calcium anacardate as source of anacardic acid, when added up to 1% in the diet, does not affect the performance and quality of the eggs of Japanese laying quails.
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Teixeira, Claudener Souza. "Determinação da estrutura tridimensional de uma lectina de sementes de Canavalia maritima (Aublet) complexada com o polifenol antioxidante resveratrol." reponame:Repositório Institucional da UFC, 2015. http://www.repositorio.ufc.br/handle/riufc/19408.
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TEIXEIRA, Claudener Souza. Determinação da estrutura tridimensional de uma lectina de sementes de Canavalia maritima (Aublet) complexada com o polifenol antioxidante resveratrol. 2015. 94 f. Tese (Doutorado em Bioquímica)-Universidade Federal do Ceará, Fortaleza, 2015.<br>Submitted by Vitor Campos (vitband@gmail.com) on 2016-09-01T23:33:14Z
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Previous issue date: 2015<br>Resveratrol is a natural antioxidant polyphenol found especially in grape epicarp, walnuts, and pomegranates, which can inhibit the activation of proinflammatory mediators and cytokines at the early gene expression stage. It is well known that lectins are sugar-binding proteins that act as both pro- and anti-inflammatory molecules. Thus, the objective of this work was to verify the binding of a polyphenol compound with a lectin of Canavalia maritima (ConM) based on their ability to inhibit pro-inflammatory processes. To accomplish this, ConM was purified and crystallized, and resveratrol was soaked at 5 mM for 2 hours of incubation. The crystal belongs to the monoclinic space group C2, the final refinement resulted in an Rfactor of 16.0% and an Rfree of 25.5%. Resveratrol binds in the rigid β-sheet through H-bonds and hydrophobic interaction with amino acids that compose the fifth and sixth β-strands of the rigid β-sheet of ConM. The ConM and resveratrol inhibited DPPH oxidation, showing synergic activity with the most effective ratio of 2:3 and carbohydrate binding site is not directly related to antioxidant activity. It is the interaction between ConM and resveratrol that indicates the synergism of these two molecules in acting as free radicals scavengers and in reducing the inflammatory process through the inhibition of many pro-inflammatory events.<br>O resveratrol é um polifenol antioxidante natural encontrado especialmente na epicarpo da uva, em nozes e na romã o qual pode inibir a ativação de mediadores pró-inflamatório e citocinas na fase precoce de expressão do gene. Já é bem conhecido que as lectinas são proteínas de ligação de açúcares que atuam tanto como moléculas pró- e anti-inflamatórias. Assim, o objetivo do presente trabalho foi o de verificar a ligação de um composto de polifenol com uma lectina de Canavalia maritima (ConM) com base na sua capacidade para inibir processos pró-inflamatórios. Para alcançar este objetivo, a ConM foi purificada e cristalizada, uma solução de 5 mM de resveratrol 5 mM foi utilizada para soaking durante 2 horas de incubação. Os cristais obtidos pertencem ao grupo espacial monoclínico C2, o refinamento final resultou em um Rfactor de 16,0% e uma Rfree de 25,5%. Resveratrol se liga na rígida através de pontes de hidrogênio e interação hidrofóbica com aminoácidos que compõem a quinta e sexta fita-β da folha-β rígida da ConM. A ConM complexada com o resveratrol inibiu a oxidação do DPPH, mostrando atividade sinérgica entre a proteína e o ligante com a relação mais eficaz de 2:3. Foi verificado ainda que o sítio de ligação a carboidratos não está diretamente relacionado à atividade antioxidante. É a interação entre ConM e resveratrol, que indica o sinergismo destas duas moléculas em agir como agentes sequestrantes de radicais livres que podem estarem relacionados a capacidade de redução do processo inflamatório através da inibição de muitos mediadores pró-inflamatórios por lecitinas.
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Guarienti, Cíntia. "Potencial antioxidante da microalga spirulina frente a condições de estresse oxidativo." reponame:Repositório Institucional da FURG, 2009. http://repositorio.furg.br/handle/1/2918.
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Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia e Ciência de Alimentos, Escola de Química e Alimentos, 2009.<br>Submitted by Caroline Silva (krol_bilhar@hotmail.com) on 2012-08-27T19:37:20Z
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Previous issue date: 2009<br>As propriedades nutricionais da microalga Spirulina têm sido relacionadas com possíveis
propriedades antioxidantes, caracterizando-a no âmbito dos alimentos funcionais. Os
antioxidantes são compostos que atuam inibindo e/ou diminuindo efeitos desencadeados pelo estresse oxidativo, conservando a harmonia entre a produção fisiológica de radicais livres e sua detoxificação. Objetivou-se avaliar o potencial antioxidante da microalga
Spirulina e seu principal pigmento, a ficocianina, em situações de estresse oxidativo induzido. Foram realizados estudos com células da levedura Saccharomyces cerevisiae, submetidas a estresse oxidativo pela adição de 1,1´-dimetil-4,4´-bipiridilo (paraquat) nas concentrações 0, 10 e 15 mM, avaliando o potencial antioxidante da Spirulina através da sobrevivência celular (plaqueamento) e da lipoperoxidação (índice de substâncias reativas ao ácido tiobarbitúrico, TBA). Também foi avaliado o efeito protetor da Spirulina e/ou da
ficocianina em córtex cerebral de ratos submetidos a estresse oxidativo por administração de glutamato monossódico ou por situação de pânico. No córtex dos animais foram avaliados os índices de TBA e a atividade específica das enzimas superóxido dismutase (SOD) e catalase (CAT). O uso do herbicida paraquat nas concentrações 10 mM e 15mM, diminuiu a sobrevivência celular da levedura em relação ao controle (39,4 % e 17,1%, respectivamente) e aumentou significativamente a lipoperoxidação (p≤0,05). O agente estressor glutamato monossódico provocou aumento significativo (p≤0,05) da lipoperoxidação e diminuição significativa (p≤0,05) das atividades específicas das enzimas SOD e CAT no córtex cerebral dos ratos. O estresse por situação de pânico também provocou alterações significativas (p≤0,05) no córtex dos ratos, aumentando a peroxidação lipídica e a atividade da enzima SOD e diminuindo a atividade da enzima CAT. O uso da Spirulina, bem como da ficocianina, atenuaram os efeitos deletérios decorrentes do estresse oxidativo induzido em células de leveduras e em córtex de ratos, mantendo os parâmetros dos grupos tratados com estressor e antioxidante
estatisticamente iguais aos do grupo controle. Estes resultados contribuem com a
caracterização da microalga no âmbito dos alimentos funcionais antioxidantes.<br>The nutritional properties of the microalgae Spirulina have been related with possible
therapeutical properties, characterizing it in the scope of functional and nutraceutical foods mainly had its antioxidant potential. The antioxidant substances are composites that act inhibiting and/or decreasing the effect unchained of oxidative stress, conserving the balance between physiological production of free radicals and its detoxification. It was objectified to evaluatethe antioxidant potential of the microalgae Spirulina and its main pigment, the phycocyanin, in situation of oxidative stress induced. studies whit cells of
Saccharomyces cerevisiae yeast had been carried, submitted oxidative stress for the
addition of 1,1´-dimetil-4,4´-bipiridilo (paraquat) in concentrations 0, 10 and 15 mM,
evaluating the antioxidant potential of the Spirulina throught the cellular survival and
reactives substances index to the tiobarbituric acid (TBA). Also was evaluated the protective effect of the Spirulina and phycocyanin, in cerebral cortex of rats submitted to oxidative stress induced for glutamate monosodic administration or panic situation. In the cortex of animals the TBA index, and activity of enzymes superoxide dismutase (SOD) and catalase (CAT) had been evaluated. The use of paraquat in concentrations 10 mM and 15mM, decreased yeast cellular survival in relation to the control (39.4% and 17.1%, respectively) and increased the lipoperoxidation significantly (p≤0,05). The estressor agent glutamate monossodic provoked significant increase (p≤0,05) in lipoperoxidation and significant reduction (p≤0,05) of enzymes SOD and CAT in the cerebral cortex of the rats. The oxidative stress for panic situation also provoked significant alterations (p≤0,05) in the cortex of the rats, increasing the lipidic peroxidation and the activity of enzyme SOD and diminishing the activity of enzyme CAT. The use of the Spirulina, as well as phycocyanin, had attenuated the decurrent deleterious effect of oxidative stress induced in cells of yeast and in cortex of rats, keeping the parameters of the groups dealt with statistical equal stressor and antioxidant substance to the ones of the group has controlled. These results
contribute with the characterization of the microalgae in the scope of antioxidant functional foods.
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Wartha, Elma Regina Silva de Andrade. "Propriedades antioxidantes de clones do pedúnculo de Anacardium occidentale L.: feito sobre a lipoperoxidação e enzimas participantes do sistema antioxidante de defesa do organismo animal." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-08062017-112859/.
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Os compostos fenólicos são substâncias amplamente distribuídas no reino vegetal, em particular nas frutas e em outros vegetais. Estes compostos, destacando-se flavonoides e os ácidos fenólicos, devido à estrutura molecular, podem apresentar a capacidade de inibir processos oxidativos. Além do mais, estão relacionados com a redução de risco de doenças crônicas não transmissíveis tais como: cardiovasculares, câncer, aterosclerose, entre outras. Considerando a elevada produção de caju em território brasileiro e a possibilidade da existência de compostos com potencial antioxidante no pedúnculo de caju , este trabalho teve por objetivo avaliar quantitativa e qualitativamente os compostos fenólicos, particularmente os ácidos fenólicos, e identificar a participação destes em processos metabólicos do organismo animal. Foram caracterizados quimicamente três clones distintos de pedúnculos de caju (CCP-76, CCP-09, BRS-189 e CCP-76 tratado) e na análise química, apresentaram um elevado teor de ácidos graxos monoinsaturados, predominando o ácido oléico, e de fenólicos totais. Os ácidos fenólicos identificados foram: gálico, protocatecuíco, p-cumárico, ferúlico, caféico e salicílico. Foram obtidos extratos aquoso (EAq) e alcoólico (EAlc) e frações de ácidos fenólicos a partir dos pedúnculos e, avaliados em sistemas modelo β-caroteno/ácidolinoléico e em Rancimat. As frações de ácidos fenólicos exibiram expressiva atividade antioxidante no primeiro sistema e os extratos, no segundo, demonstraram fatores de proteção superior ao antioxidante sintético BHT. Pôde-se também verificar a capacidade antioxidante dos extratos e frações do clone CCP-76 no sistema de varredura do radical DPPH. Em ensaio experimental com ratos, em condição normal, foi administrado EAq (80 e 240 mg/kg, v.o.) ou fração de ácidos fenólicos livres (40 e 120 mg/kg, v.o.) obtidos do pedúnculo de caju CCP-76. Neste estudo, não se observou potencialização de todos os antioxidantes enzimáticos (superóxido dismutase, catalase e glutationas peroxidase e redutase), contudo pôde-se verificar a redução dos níveis de lipoperoxidação no tecido cerebral dando indícios de aumento do estado antioxidante nos animais. Também foi avaliado o potencial antioxidante do EAq e da fração de ácidos fenólicos livres sobre o dano hepático em ratos tratados com tetracloreto (CCl4) de carbono. A administração deste teve seu efeito corroborado pela avaliação dos parâmetros bioquímicos, ou seja, aumento exacerbado das enzimas hepáticas no plasma: alanina transaminase (ALT) e aspartato transaminase (AST); decréscimo da atividades da enzimas antioxidantes no fígado e elevação da produção de peróxidos lipídicos no tecido hepático. Nos ratos que receberam EAq (480 mg/kg, v.o.) não se observou alteração comparando-os aos animais tratados apenas com CCl4 . No entanto, a administração de fração de ácidos fenólicos livres, nas duas doses (40 e 120 mg/kg, v.o.), evidenciou pronunciado efeito contra a lesão hepática, com níveis reduzidos de AL T e AST plasmáticas, aumento da atividade das enzimas antioxidantes no fígado e prevenindo a lipoperoxidação hepática mediada pelo radical CCl3• a partir do CCl4. Estudos histológicos do tecido hepático confirmaram as avaliações bioquímicas exibindo preservação tecidual, supressão de degeneração vacuolar macro e microgoticular e de sinais necróticos nos ratos tratados com a fração de ácidos fenólicos livres do pedúnculo de caju.<br>Phenolic compounds are widely distributed in the plant kingdom, particularly fruits and vegetables. Due to their chemical structure, these compounds, in particular flavonoids and phenolic acids, are able to inhibit oxidative processes. Furthermore, can be used to reduce the risk of non-transmissible chronic diseases such as cardiovascular diseases, cancer and atherosclerosis. Taking into consideration the large production of cashew in Brazil and the possible existence of potentially antioxidant compounds present in the cashew apples, the aim of this study was to quantitatively and qualitatively evaluate the presence of phenolic compounds in cashew apple, particularly phenolic acids, and identify their role in metabolic processes in animals. The cashew apples of three distinct clones (CCP-76, CCP-09, BRS-189 and CCP-76 (processed)) were studied. The determination of fatty acids yielded a high concentration of monounsaturated fatty acids, mainly oleic acid, and of total phenolic compound. The phenolic acids found were: gallic, proteocatechuic, p-cumaric, ferulic, caffeic and salicylic acids. Both aqueous (EAq) and ethanolic (EAlc) extracts and phenolic acid fractions were obtained from the cashew apples and were evaluated in a β-carotene/linoleate model system and Rancimat test. The phenolic acid fractions presented an expressive antioxidant activity in the β-carotene/linoleate model system and the extracts, by the Rancimat test presented a protection factor higher than that of antioxidant additive, BHT. We also observed the antioxidant capacity of the extracts and fractions of the CCP-76 clone in the DPPH radical scavenging assay. In an experimental assay with rats, the EAq (80 and 240 mg/kg) or the free phenolic acid fraction (40 and 120 mg/kg) obtained from the cashew apple of CCP-76 clone was administered via the oral route. In this study, the enhancement of enzymatic antioxidants (superoxide dismutase, catalase, glutathione peroxidase and reductase) was not observed, nevertheless, a decrease in the amount of lipoperoxidation in the brain tissue was observed, suggesting that the ingestion of cashew might increase the antioxidative state in animals. Also, the antioxidant activity of EAq and of the free phenolic acid fraction from the cashew apple of CCP-76 clone was verified on the liver damage induced by carbon tetrachloride. The liver damage caused by the administration of carbon tetrachloride was detected by biochemical parameters, namely, the increase in the serum concentrations of alanine transaminase (ALT) and aspartate transaminase (AST) as well as a decrease in the activities of antioxidant enzymes and an increase in peroxidation in the liver. Rats who received EAq (480 mg/kg, p.o.) did not present alterations in any of the parameters evaluated, compared to the animals treated with carbon tetrachloride. On the other hand, the administration of free the phenolic acid fraction in doses of 40 and 120 mg/kg, p.o., had a pronounced effect in protecting against hepatic lesion, which was evidenced by the decrease in plasma ALT and AST, enhancing the activity of antioxidant enzymes and preventing lipoperoxidation mediated by the CCl3• radical generated by carbon tetrachloride. Histological studies were able to confirm the biochemical alterations observed in that the liver tissue obtained from rats treated with phenolic acid fractions extracted from cashew apple of CCP-76 clone presented a preserved tissue structure and suppression of macro and microgoticular vacuolar degeneration as well as of signs of necrosis.
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Martins, Carolina de Aguiar. "Avaliação da atividade antioxidante in vitro e in vivo do guaraná (Paullinia cupana) em pó." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/6/6138/tde-31012011-093906/.
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Introdução Estudos indicam que antioxidantes presentes naturalmente em alguns alimentos são capazes de atuar como protetores dos organismos vivos frente aos danos causados pelo estresse oxidativo em macromoléculas como lipídios, proteínas e em DNA. O guaraná (Paullinia cupana), planta originária da Amazônia, contém elevadas concentrações de taninos e cafeína, compostos com comprovada atividade antioxidante. Apesar do aumento no consumo de guaraná e de estudos associando seus efeitos benéficos à saúde, há poucas informações sobre suas propriedades antioxidantes in vivo. Objetivos: avaliar o efeito do consumo de bebida a base guaraná em pó em humanos. Métodos - In vitro: amostras de guaraná em pó foram analisadas para determinação da composição proximal; conteúdo de compostos fenólicos totais (Folin-Ciocalteau) e atividade antioxidante pelo ensaio DPPH foram determinados em amostras extraídas com água, metanol, etanol 60 por cento e acetona 35 por cento. In vivo e ex vivo: amostras de sangue de voluntários saudáveis (n=12) foram coletadas em jejum (J1) e 1h após o consumo da bebida com guaraná em pó foram coletadas novamente amostrar de sangue (G1). Após 15 dias da ingestão diária da bebida foram realizadas duas novas coletas, uma em jejum (J15) e outra após a primeira hora de consumo da bebida (G15). Foi avaliada a resistência da LDL à oxidação ex vivo iniciada com cobre pelo ensaio de dienos conjugados. O perfil antioxidante total (TAS) e a capacidade de absorbância de radical oxigênio (ORAC) foram determinados no plasma dos voluntários. Ensaio Cometa foi realizado para verificar danos oxidativos ao DNA em linfócitos dos voluntários. A atividade das enzimas Superóxido Dismutase (SOD), Catalase (Cat) e Glutationa Peroxidase (GPx) foi determinada em eritrócitos. Os resultados das diferentes análises foram apresentados com média e desvio-padrão. Foram utilizados ANOVA e teste de Tukey para verificar se há diferença no teor de compostos fenólicos totais e na atividade antioxidante das amostras extraídas com diferentes solventes. As verificações de aderência à curva normal foram realizadas pelo teste de KolmogorovSmirnov. As comparações das variáveis de distribuição normal para as amostras pareadas foram baseadas no teste t de Student. Para todas as inferências foi utilizado o nível de significância menor ou igual a 5 por cento. Para todos estes cálculos estatísticos foi utilizado o programa SPSS versão 16.0 for Windows. Resultados: Foi observado aumento significativo no lag time de oxidação da LDL tanto após uma hora do consumo da primeira dose de guaraná em pó quanto após uma hora do consumo no 15º dia de intervenção (G1>J1, G15>J15; p<0,05). O consumo de uma única dose de guaraná aumentou significativamente a atividade da Cat nos tempos G1 e G15 (p < 0,05) e da GPx no tempo G15 (p<0,05). Após intervenção com doses repetidas durante 15 dias houve aumento significativo da atividade da Cat e da GPx no jejum do último dia de intervenção quando comparado ao jejum do baseline (J15>J1; p<0,05). O consumo de guaraná não influenciou a atividade da SOD, tampouco o TAS (p>0,05). O consumo da bebida apresentou efeito agudo sobre o ORAC, uma vez que houve aumento significativo desse parâmetro tanto após uma hora do consumo da primeira dose de guaraná em pó quanto após uma hora do consumo no 15º dia de intervenção (G1>J1, G15>J15; p<0,05). O ORAC no plasma dos voluntários e avaliação de danos oxidativos ao DNA com desafio por peróxido de hidrogênio apresentaram o mesmo comportamento da resistência da LDL à oxidação: apenas efeito agudo foi observado pelo consumo da bebida (G1>J1, G15>J15; p<0,05). Sugere-se que o fracionamento da dose de guaraná em pó seja mais eficiente do que o consumo de uma única dose no dia para a manutenção da concentração dos compostos fenólicos no plasma a fim de promover efeitos pelo consumo de doses repetidas. Os efeitos antioxidantes pelo consumo de uma única dose de guaraná em pó parecem se extender além do tempo de depuração dos compostos fenólicos no plasma. São necessárias ainda novas pesquisas a fim de avaliar a dose e o tempo de intervenção para que sejam observados efeitos em humanos pela ingestão de doses repetidas de guaraná<br>Introduction Studies indicate that antioxidants found naturally in some foods are capable of acting as protectors of living organisms against oxidative stress in macromolecules such as lipids and proteins and in DNA. Guarana (Paullinia cupana), a plant from Amazonia, contains high concentrations of tannins and caffeine, compounds with proven antioxidant activity. Despite the increase in consumption of guarana and studies linking their beneficial health effects, there is little information on its antioxidant properties in vivo. Objectives: investigate the effects of guarana consumption in humans. Methods: In vitro: guarana powder samples were analyzed for proximal composition; content of total phenolics (Folin- Ciocalteau) and antioxidant activity by DPPH assay were determined in samples extracted with water, methanol, ethanol 60 per cent and acetone 35 per cent. In vivo and ex vivo: blood samples from healthy volunteers (n = 12) were collected at a twelve-hour overnight fast (J1) and 1h after consumption of the drink with guarana powder the second blood sample was collected (G1). After 15 days of daily ingestion of the drink other two samples were collected: a twelve-hour overnight fast (J15) and again after the first hour of drink consumption (G15). The resistance of LDL to ex vivo oxidation initiated by copper was evaluated. The total antioxidant status (TAS) and the oxygen radical absorbance capacity (ORAC) were determined in plasma of volunteers. Comet assay was conducted to determine oxidative DNA damage in lymphocytes of volunteers. The activity of superoxide dismutase (SOD), catalase (Cat) and glutathione peroxidase (GPx) was determined in erythrocytes. ANOVA and test of Tukey were used to verify if there was significant differences in total phenolic contents and antioxidant activity of samples extracted with different solvents. The verification of adherence to the normal curve were performed by the Kolmogorov-Smirnov test. Comparisons of variables of normal distribution for the paired samples were based on t test of Student. For all inferences the significance level was less than or equal to 5 per cent. For all these calculations the statistical program SPSS version 16.0 for Windows was used. Results: Significant increase in lag time of LDL oxidation was observed, both after one hour of consumption of the first dose of guarana powder and after one hour of consumption in the 15th day of intervention (G1> J1, G15> J15, p <0.05). The consumption of a single dose of guarana significantly increased the activity of Cat in the times G1 and G15 (p<0.05). After intervention with repeated doses during 15 days, there was a significantly increase in the activity of Cat and GPx in fasting of the last day intervention compared to baseline fasting (J15> J1, p<0.05). The consumption of guarana didnt influence the activity of SOD neither the TAS (p>0.05). The ORAC in plasma of volunteers and assessment of oxidative damage to DNA challenge with hydrogen peroxide showed the same behavior of the resistance of LDL to oxidation: only acute effect was observed by the consumption of the drink (G1> J1, G15> J15, p<0.05). It is suggested that the fractionation of the dose of guarana powder is more efficient than the consumption of a single dose on day to maintain the concentration of phenolic compounds in plasma to promote the consumption effects of repeated doses. The antioxidant effects by consumption of a single dose of guarana powder seem to extend beyond the time of clearance of phenolic compounds in plasma. New reserches are needed in order to evaluate the dose and duration of intervention for being observed effects in humans by ingestion of repeated doses of guarana
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Nälsén, Cecilia. "Measurement and evaluation of antioxidant status and relation to oxidative stress in humans /." Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6742.
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Badia, Pérez Anna. "Antioxidant nanoparticles for the treatment of Age-related Macular Degeneration: preclinical studies in the DKOrd8 mouse model." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/670132.
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La Degeneració Macular Associada a la Edat (DMAE) és una malaltia ocular degenerativa d’aparició tardana que afecta la retina central i causa una pèrdua progressiva de visió. La DMAE és una malaltia multifactorial en la qual l’envelliment és un dels principals factor de risc i on l’estrés oxidatiu, l’autofàgia i el sistema immunitari tenen una important rellevància en la seva patogènesis. L’exposició constant de llum que pateix la màcula exigeix una elevada activitat metabòlica per part dels fotoreceptors i l’EPR, cosa que genera nivells elevats d’estrés oxidatiu amb un increment de les espècies reactives d’oxigen (ROS). Això indueix canvis a la retina, incloent la acumulació de lipofuscina, una desregulació de l’autofàgia, la presència de druses i inflamació crònica; cosa que acaba provocant la mort del EPR i dels fotoreceptors. Malgrat ser la principal causa de ceguera en els països desenvolupats, encara no existeix un tractament efectiu per a la DMAE. La falta de coneixement sobre els mecanismes implicats en l’aparició de la malaltia així com la falta de models animals recapitulant el fenotip n’han estat els principals obstacles. En els últims anys, els compostos antioxidants han adquirit importància donat el rol que l’estrés oxidatiu juga en l’aparició de la malaltia. Sota aquestes premisses, els objectius d’aquesta tesis han estat (i) la generació i caracterització del ratolí Ccl2-/-; Cx3cr1-/-; Crb1rd8\/rd8, un model murí per a la DMAE; i (ii) el desenvolupament d’una teràpia basada en nanopartícules amb gran capacitat antioxidant. En primer lloc, vam generar el model Ccl2-/-; Cx3cr1-/-; Crb1rd8/rd8 o DKOrd8 a partir dels knockout simples. Mitjançant la seva monitorització in vivo i caracterització post-mortem, vam observar com els ratolins DKOrd8 presentaven diverses característiques fenotípiques típiques de la DMAE al mes d’edat. Els ratolins DKOrd8 presentaven alteracions a l’hemisferi inferior del fons d’ull amb disrupció de la capa de fotoreceptors i una disminució progressiva del seu gruix. Mitjançant immunofluorescència vam observar una acumulació de micròglia a l’espai subretinià, una migració cap a les lesions de la retina i un increment de gliosis. A més, els ratolins DKOrd8 exhibien alteracions en el patró d’expressió gènic, amb afectació en gens relacionats amb l’estrés oxidatiu, el sistema immunitari i les funcions neuronals entre d’altres. En relació al desenvolupament de la teràpia antioxidant, vam sintetitzar unes nanopartícules antioxidants (AOxNPs) no tòxiques amb una capacitat reproduïble de disminuir els nivells intracel·lulars de ROS en cultius in vitro. A més, vam establir l’administració tòpica com una ruta eficient per arribar a la retina, comparable a la injecció intravítria. Finalment, el tractament tòpic amb AOxNPs en els ratolins DKOrd8 va demostrar ser efectiva, aconseguint revertir el patró d’expressió alterat, disminuir la infiltració de micròglia i prevenint l’aprimament de la capa nuclear externa. En conjunt, en aquest treball hem aconseguit generar un model fiable que presenta certes característiques típiques de la DMAE i hem demostrat l’efecte beneficiós de l’administració tòpica de les AOxNPs en la millora de les característiques patològiques del model.<br>La Degeneración Macular Asociada a la Edad (DMAE) es una enfermedad ocular degenerativa de aparición tardía que afecta a la retina central y causa una pérdida progresiva de visión. La DMAE es una enfermedad multifactorial en la que el envejecimiento es uno de los principales factores de riesgo y en la que el estrés oxidativo, la autofagia y el sistema inmunitario tienen una importante relevancia en su patogénesis. La exposición constante a la luz que sufre la mácula exige una elevada actividad metabólica por parte de los fotorreceptores y del EPR, lo que genera niveles elevados de estrés oxidativo con un incremento de las especies reactivas de oxigeno (ROS). Esto induce cambios en la retina, incluyendo la acumulación de lipofuscina, una desregulación de la autofagia, la presencia de drusas e inflamación crónica; cosa que acaba causando la muerte del EPR y de los fotorreceptores. Aunque es la principal causa de ceguera en países desarrollados, aun no existe un tratamiento efectivo para la DMAE. La falta de conocimiento sobre los mecanismos implicados en la aparición de la enfermedad así como la falta de modelos animales recapitulando el fenotipo han sido los principales obstáculos. En los últimos años, los compuestos antioxidantes han adquirido importancia dado el rol que el estrés oxidativo juga en la aparición de la DMAE. Bajo estas premisas, los objetivos de esta tesis han estado (i) la generación y caracterización del ratón Ccl2-/-; Cx3cr1-/-; Crb1rd8/rd8, un modelo murino para DMAE; y (ii) el desarrollo de una terapia basada en nanopartículas con gran capacidad antioxidante. En primer lugar, generamos el modelo Ccl2-/-; Cx3cr1-/-; Crb1rd8\/rd8 o DKOrd8 a partir de los knockout simples. Mediante su monitorización in vivo y caracterización post-mortem, observamos cómo los ratones DKOrd8 presentaban varias características fenotípicas típicas de la DMAE al mes de edad. Los ratones DKOrd8 presentaban alteraciones en el hemisferio inferior del fondo de ojo con disrupción de la capa de fotorreceptores y una disminución progresiva de su grosor. Mediante inmunofluorescencia observamos una acumulación de microglía en el espacio subretiniano y migración hacia las lesiones de la retina y un incremento de gliosis. Además, los ratones DKOrd8 exhibían alteraciones en el patrón de expresión génica, con afectación en genes relacionados con el estrés oxidativo, el sistema inmunitario y las funciones neuronales entre otros. En relación al desarrollo de la terapia antioxidante, sintetizamos unas nanopartículas antioxidantes (AOxNPs) no tóxicas con capacidad reproducible de disminuir los niveles intracelulares de ROS en cultivos in vitro. Además, establecimos la administración tópica como una ruta eficiente para la llegada a la retina, comparable a la inyección intravítrea. Finalmente, el tratamiento tópico con AOxNPs en los ratones DKOrd8 demostró ser efectivo, consiguiendo revertir el patrón de expresión alterado, disminuir la infiltración de microglía y prevenir el adelgazamiento de la capa nuclear externa. En conjunto, en este trabajo hemos conseguido generar un modelo fiable que presenta ciertas características típicas de la DMAE y hemos demostrado el efecto beneficioso de la administración tópica de las AOxNPs en la mejora de las características patológicas del modelo.<br>Age-related Macular Degeneration (AMD) is a late-onset degenerative eye disease that affects the central retina and causes progressive vision impairment. AMD is a multifactorial disease, with advanced age being the main risk factor and oxidative stress, autophagy and the immune system playing an important role in its pathogenesis. The constant exposure to light in the macula demands a high metabolic rate for photoreceptors and RPE cells, which generate elevated levels of oxidative stress. These increased levels of ROS induce several changes in the retina, including the accumulation of lipofuscin, the deregulation of autophagy, the presence of drusen and chronic inflammatory responses that end up causing RPE cells death and photoreceptor loss. Despite being the major cause of blindness in developed countries, AMD still does not have an effective treatment available. The lack of knowledge about the mechanisms implicated in the onset of the disease and the lack of animal models recapitulating the phenotype of the disease have been the major obstacles. In the last years, antioxidant compounds have gained importance given the role oxidative stress plays on the onset of the disease. Under these premises, the aim of this thesis was set on (i) the generation and characterization of the Ccl2-/-; Cx3cr1-/-; Crb1rd8\/rd8 mouse, a murine model for AMD; and (ii) the development of a therapy based on nanoparticles with high antioxidant capacity. The Ccl2-/-; Cx3cr1-/-; Crb1rd8/rd8 or DKOrd8 model was generated from the single knockout mice. Its posterior in vivo monitoring and post-mortem characterization revealed that DKOrd8 mice mimicked several AMD-like features already at one month of age. DKOrd8 mice presented alterations in the inferior hemisphere of their eye fundus with disruption and age-dependent decrease of the photoreceptor layer; and alterations in their retinal function at an early age that were maintained upon ageing. Immunofluorescence stainings revealed an age-dependent accumulation of microglia in the subretinal space, migration of the microglia towards the inner retinal lesions and increased gliosis. Moreover, DKOrd8 mice exhibit an altered expression pattern with an affectation of genes involved with oxidative stress, immune regulation and neuronal function among others. Regarding the development of the antioxidant therapy, we synthetize non-toxic antioxidant nanoparticles (AOxNPs) with a reproducible capacity of reducing intracellular ROS levels in in vitro cultures and established the topical administration as an efficient delivery route to reach the retina and posterior segment of the eye comparable to the intravitreal injection. Finally, the topical treatment of DKOrd8 mice with AOxNPs was effective in improving the phenotypical characteristics of the mouse model, as it reverted their altered expression profile, reduced microglia infiltration and prevented the thinning of the outer nuclear layer. Altogether, we generated a reliable mouse model that mimicked certain features of AMD and proved the beneficial effect of the topical AOxNPs in improving the pathological characteristics of the model.
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Nagah, Abdulbaset M. S. "Antioxidant properties of wholegrain foods and the effect of wholegrain consumption on antioxidant status." Thesis, University of Newcastle Upon Tyne, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419959.
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Sirdaarta, Joseph P. "Phytochemical Study and Anticancer Potential of High Antioxidant Australian Native Plants." Thesis, Griffith University, 2016. http://hdl.handle.net/10072/365567.
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High antioxidant capacities have been linked with a reduction in the incidence of chronic diseases including cardiovascular disease, diabetes, obesity, neurodegeneration, inflammation and cancer. Furthermore, phenolic antioxidants may not only have protective effects against these diseases, but may also have therapeutic potential in reversing them by modulation of the cellular redox state. Thus, plants with high antioxidant capacities have potential in the development of new chemotherapeutic treatments to prevent and treat some cancers. Several native Australian plant species including Terminalia ferdinandiana Exell (Kakadu plum), Tasmannia lanceolata (Poir.) A.C.Sm., (Tasmannian pepper), Syzygium australe (H.L.Wendl. ex Link) B.Hyland (brush cherry), Syzygium luehmannii (F.Muell.) L.A.S.Johnson (riberry), Davidsonia pruriens F.Muell. (Davidson’s plum), Elaeocarpus angustifolius Blume (quandong), Kunzea pomifera F.Muell. (muntries), Podocarpus elatus R.Br.ex Endl., (Illawarra plum) and Acronychia acidula F.Muell., (lemon aspen) have recently been reported to have extraordinarily high antioxidant content and were therefore selected to screen for the ability to inhibit proliferation of selected carcinoma cell lines.<br>Thesis (PhD Doctorate)<br>Doctor of Philosophy (PhD)<br>School of Natural Sciences<br>Science, Environment, Engineering and Technology<br>Full Text
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Gual, Frau Josep. "Efecto de la microvaricocelectomía y el tratamiento antioxidante oral en el adn espermático en pacientes infértiles con varicocele." Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/669516.
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Introducció
El varicocele és una de las majors causes d'infertilidad masculina. El tractament quirúrgic del varicocele està indicat en pacients amb infertilitat i varicocele clínic o palpable. La microcirurgía del varicocele ha demostrat ser la millor tècnica per a la seva reparació.
El varicocele grau I o subclínic, al què no es recomana el tractament quirúrgic, també pot ser causa d'infertilidad. El tractament antioxidant ha demostrat millories a la qualitat seminal de pacients infèrtils, però no hiha dades del seu efecte en pacients amb varicocele.
Les espècies reactives d'xigen que es generen en augment en pacients amb varicocele, poden danyar l'ADN espermàtic, principalment a través de modificacions a la guanina. Al nostre grup, vam postular què l'efecte de dany a l'ADN podia ser més intens als telòmers, donat que els telmeros són rics en guanina, fet que podroa comprometre la fertilitat.
Hipòtesi i Objectius
Coneixent les anteriors afirmacions, s'ha intentat analitzar per una banda l'efecto de la microvaricocelectomia sobre la longitut telomèrica i fragmentació de l'ADN espermàtic, així com el seu efecte al seminograma i, per una altra banda, en aquells pacients amb varicocele subclínic, s'ha intentat comprovar l'efecto del tractament antioxidant tant al seminograma como a la fragmentació de l'ADN espermàtico.
Material y Mètodes
S'han incluido a l'estudi 12 donants de semen fèrtils i 40 pacients amb varicocele associat a infertilitat i s'han dividit en 2 grups.
Grup 1: 20 pacients amb varicocele clínic, als quals s'ha analitzat abans i 9 mesos després del tractament quirúrgic mitjançant microvaricocelectomia, els valors del seminograma, la fragmentació de simple i doble cadena i la longitut telomèrica de l'ADN espermàtic.
Grup 2: 20 pacients amb varicocele subclínic, als quals s'ha analitzat abans i 3 mesos després del tractament antioxidant oral mitjançant un complexe multivitamínic, els valors del seminograma i la fragmentació d'ADN espermàtic.
Resultats
En comparació a donants fèrtils, el varicocele no té una reducció significativa de la longitut telomèrica. Respecte a la microvaricocelectomia, tampoc ha demostrat canvis en dita longitud. No obstant això, si s'han observat canvis estadísticament significatius en quant als valors del seminograma i de la fragmentació d'DN espermàtic, tant de simple com de doble cadena.
En quant al tractament antioxidant en els pacients amb varicocele subclínic, ha demostrat una reducció significativa de la fragmentació de l'espermàtic, mentre queal seminograma, només es van observar canvis a favor del tractament al nombre total de espermatozous, sense que es veieren alterats la resta de valors del seminograma.
Conclusions
En base als nostres resultats, podems afirmar què a la nostra sèrie no hem trobat un efecte del varicocele i del seu tractament quirúrgic sobre la longitut telomèrica de l’ADN espermàtic. Si que hem confirmat la milloria a les xifres de fragmentació de l'ADN espermàtic de simple i doble cadena i millories al seminograma gràcies al tractament.
Per una altra banda, les dades sugereixen què la integritat de l'ADN espermàtic al varicocele grau I millora amb el tractament antioxidant oral."<br>Introducción
El varicocele es una de las mayores causas de infertilidad masculina. El tratamiento quirúrgico del varicocele está indicado en pacientes con infertilidad y varicocele clínico o palpable. La microcirugía del varicocele ha demostrado ser la mejor técnica para su reparación.
El varicocele grado I o subclínico, en el que no se recomienda el tratamiento quirúrgico, también puede ser causa de infertilidad. El tratamiento antioxidante ha demostrado mejorías en la calidad seminal de pacientes infértiles, pero no hay datos de su efecto en pacientes con varicocele.
Las especies reactivas de oxígeno que se generan en aumento en pacientes con varicocele, pueden dañar el ADN espermático, principalmente a través de modificaciones en la guanina. En nuestro grupo, postulamos que el efecto de daño en el ADN podía ser más intenso en los telómeros, dado que los telómeros son ricos en guanina, hecho que podría comprometer la fertilidad.
Hipótesis y Objetivos
Conociendo las anteriores afirmaciones, se ha intentado analizar por un lado el efecto de la microvaricocelectomía sobre la longitud telomérica y fragmentación del ADN espermático, así como su efecto el seminograma; y por otro lado, en aquellos pacientes con varicocele subclínico, se ha intentado comprobar el efecto del tratamiento antioxidante tanto en el seminograma como en la fragmentación del ADN espermático.
Material y Métodos
Se han incluido en el estudio 12 donantes de semen fértiles y 40 pacientes con varicocele asociado a infertilidad y se han dividido en 2 grupos.
Grupo 1: 20 pacientes con varicocele clínico, en los cuales se ha analizado antes y 9 meses después del tratamiento quirúrgico mediante microvaricocelectomía, los
valores del seminograma, la fragmentación de simple y doble cadena y la longitud telomérica del ADN espermático.
Grupo 2: 20 pacientes con varicocele subclínico, en los cuales se ha analizado antes y 3 meses después del tratamiento antioxidante oral mediante un complejo multivitamínico, los valores del seminograma y la fragmentación de ADN espermático.
Resultados
En comparación a donantes fértiles, el varicocele no tiene una reducción significativa de la longitud telomérica. Respecto a la microvaricocelectomía, tampoco ha demostrado cambios en dicha longitud. Sin embargo, sí se han observado cambios estadísticamente significativos en cuanto a los valores del seminograma y de la fragmentación de ADN espermático, tanto de simple como de doble cadena.
En cuanto al tratamiento antioxidante en los pacientes con varicocele subclínico, ha demostrado una reducción significativa de la fragmentación del ADN espermático, mientras que en el seminograma, solamente se observaron cambios a favor del tratamiento en el número total de espermatozoides, sin que se vieran alterados el resto de valores del seminograma.
Conclusiones
En base a nuestros resultados, podemos afirmar que en nuestra serie no hemos encontrado un efecto del varicocele y de su tratamiento quirúrgico sobre la longitud telomérica del ADN espermático. Sí que hemos confirmado la mejoría en las cifras de fragmentación del ADN espermático de simple y doble cadena y mejorías en el seminograma gracias al tratamiento.
Por otro lado, los datos sugieren que la integridad del ADN espermático en el varicocele grado I mejora con el tratamiento antioxidante oral.<br>Introduction
Varicocele is one of the main causes of male infertility. The surgical treatment of varicocele is indicated for patients with infertility in combination with clinical or palpable varicocele. Mycrosurgurgical varicocelectomy has demonstrated to be the best procedure for its repair.
Grade I varicocele o subclinical, in which it is not recommended this surgical treatment, could be as well an infertility cause. Antioxidant treatment has demonstrated seminal quality improvements, but there is no prior data to investigate the effect on varicocele patients.
Reactive oxygen species, that are highly generated in varicocele patients, can damage sperm DNA, principally due to guanine modifications. In our group, we thought that the effect of DNA damage could be more intense because the telomeres are rich in guanine, fact that could also compromise fertility.
Hypothesis and Objectives
In the view of the above, in one hand, we tried to analyze the effect of microvaricocelectomy to the telomere length and sperm DNA fragmentation, and its effect on seminal parameters. On the other hand, in subclinical varicocele patients, we tried to assess the effect of antioxidant treatment in seminal parameters and in sperm DNA fragmentation.
Material and Methods
For this purpose, 12 fertile donors and 40 infertile varicocele patients were included in the study and divided in two groups:
Group 1: 20 clinical varicocele patients, in which we analyzed, before and 9 months after microvaricocelectomy surgical treatment, seminal parameters, sperm simple and double-strand DNA fragmentation and telomere length.
Group 2: 20 subclinical varicocele patients, in which we analyzed, before and after 3 months of oral antioxidant treatment with a multivitamin complex, seminal parameters and sperm DNA fragmentation.
Results
Comparing with fertile donors, varicocele had no effect on telomere length. Results showed that microsurgical varicocelectomy had no effect on telomere length before and after treatment. However, we observed significant statistical differences in seminal parameters and sperm simple and double DNA fragmentation.
Referring to antioxidant treatment in subclinical varicocele patients, we demonstrated a significant reduction on sperm DNA fragmentation, whilst we only observed changes in total sperm count in favor to the treatment, without observing changes in the rest of seminal parameters.
Conclusions
On the basis of the findings, we are able to affirm that in our series we have not found an effect of varicocele and its surgical treatment over sperm ADN telomere length. We have confirmed improvements in sperm DNA simple and double strand fragmentation levels due to surgical treatment and improvements on seminal parameters.
Moreover, data suggest that sperm DNA integrity, in varicocele grade I patients, improve with oral antioxidant treatment.
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O'Reilly, James Daniel. "Antioxidant activity of dietary flavonoids." Thesis, King's College London (University of London), 1999. https://kclpure.kcl.ac.uk/portal/en/theses/antioxidant-activity-of-dietary-flavonoids(10c771a4-169d-405b-a1cd-354e86ebd109).html.
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Re, Roberta. "Lycopene : antioxidant properties and bioavailability." Thesis, King's College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248044.
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Kennedy, Todd Allen. "Antioxidant functions of beta-carotene." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185589.
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The provitamin A carotenoid β-carotene is an attractive candidate for the prevention of cancer. Indeed, abundant evidence suggests that β-carotene inhibits carcinogenesis. β-Carotene is thought to inhibit carcinogenesis by scavenging free radicals involved in tumor formation. However, there is no direct evidence that β-carotene traps radicals under conditions where it inhibits carcinogenesis. The overall objective of this dissertation research was to identify β-carotene oxidation products from β-carotene antioxidant reactions in model systems. Identification of such products will enable the direct measurement of β-carotene antioxidant activity in systems where it inhibits neoplastic transformation. In hexane solution, β-carotene was oxidized by peroxyl radicals to 5,6-epoxy-β, β-carotene, 15,15'-epoxy-β, β-carotene, a previously unreported product, and several unidentified polar products. Studies on the kinetics of product formation suggested that polar products are formed by both epoxide-dependent and -independent pathways. Because β-carotene may be localized within lipid bilayers in vivo, peroxyl radical oxidation of β-carotene in model membranes was examined. In soy phosphatidylcholine liposomes, β-carotene was oxidized by peroxyl radicals to the 5,6-epoxide and to unidentified polar products. β-Carotene antioxidant activity in the liposome system was the same at 15 torr and 160 torr O₂ and decreased at 760 torr O₂. These results suggest that β-carotene provides equal antioxidant protection in all tissues in vivo. The relative rates of product formation and β-carotene oxidation at different pO₂ suggested that β-carotene antioxidant activity is governed by the relative proportions of β-carotene radical trapping and autoxidation reactions, which do not contribute to radical trapping. Therefore, the loss of β-carotene antioxidant action at 760 torr O₂ may result from an increase in β-carotene oxidation by autoxidation pathways. The 5,6-epoxide was formed during both antioxidant reactions and autoxidation reactions and may be marker for the peroxyl radical oxidation of β-carotene. Attempts to study β-carotene antioxidant reactions in biological membranes were only partially successful. In vitro incorporation of β-carotene into microsomes was attempted by several methods. However, these efforts resulted in only modest β-carotene antioxidant activity in microsomes. These studies provide a basic understanding of β-carotene antioxidant chemistry in model systems. Their results will enable further investigation of β-carotene antioxidant action in biological systems.
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Wattamwar, Paritosh P. "SYNTHESIS AND CHARACTERIZATION OF POLYMERIC ANTIOXIDANT DELIVERY SYSTEMS." UKnowledge, 2011. http://uknowledge.uky.edu/cme_etds/2.
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Even though the role of oxidative stress in a variety of disease states is known, strategies to alleviate this oxidative stress by antioxidants have not been able to achieve clinical success. Particularly, treatment of oxidative stress by small molecule antioxidants has not received due attention because of the challenges associated with its delivery. Antioxidant polymers, where small molecule antioxidants are incorporated into the polymer backbone, are an emerging class of materials that can address some of these challenges.
In this work, biodegradable polymers incorporating phenolic antioxidants in the polymer backbone were synthesized. Antioxidant polymers were then characterized for their in vitro degradation, antioxidant release and their effect on oxidative stress levels (redox state) in the cells. Trolox, a water-soluble analogue of vitamin E, was polymerized to synthesize poly(trolox ester) with 100% antioxidant content which undergoes biodegradation to release trolox. Nanoparticles of poly(trolox ester) were able to suppress oxidative stress injury induced by metal nanoparticles in an in vitro cell injury model.
In another study, we polymerized polyphenolic antioxidants (e.g. curcumin, quercetin) using a modified non-free-radical polymerization poly(β-amino ester) chemistry. This synthesis scheme can be extended to all polyphenolic antioxidants and allows tuning of polymer degradation rate by choosing appropriate co-monomers from a large library of monomers available for β-amino ester chemistry. Poly(antioxidant β-amino esters) (PABAE) were synthesized and characterized for their degradation, cytotoxicity and antioxidant activity. PABAE degradation products suppressed oxidative stress levels in the cells confirming antioxidant activity of degradation products.
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Kováčová, Ivana. "Stanovení biologicky aktivních látek ve vybraných přírodních rostlinných extraktech." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-240571.
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This thesis is focused on the study of the effectiveness of active ingredients from natural extracts such as milk thistle and turmeric. The thesis describes the use of modern methods of analysis and identification of active substances located in plants of milk thistle and turmeric. In the experimental part of thesis, which was preceded by a literature search focused on the biological effects of active substances in the chosen natural extracts, the extracts were characterized according to group characteristics (total assessment of polyphenols and flavonoids, assessment of antioxidant activity, and assessment of vitamin C volume and tocopherol). The next part is focused on the study of the encapsulation of natural active substances into the organic particles: liposomes. Silymarin and curcumin were encapsulated as active substances. The idea of a plant with a single active ingredient is usually erroneous. Plants usually contain hundreds of components which cooperate on a given effect. Therefore, the majority of herbalists believe that a simple plant is an active ingredient. However, some plants are known to be containing a particular active phytochemical. For instance, plants such as the milk thistle, turmeric, or a ginkgo are great examples of the plant containing a particular active phytochemical. In these cases, the active compound is disproportionately more effective than the plant itself. Encapsulation efficiency of active ingredients of Silymarin and curcumin was determined by HPLC/PDA. The aim of the analysis was to observe the behavior of elements during the incubation in surrounding of gastric juice model, and the stability while maintaining the particles in model food.
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SILVA, Tacila Mendes da. "Caracterização fenólica e capacidade antioxidante de vinhos tintos do Hemisfério Sul." Universidade Federal de Pernambuco, 2015. https://repositorio.ufpe.br/handle/123456789/15685.
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Previous issue date: 2015-06-22<br>CAPES<br>A vitivinicultura, comumente praticada em países da Europa, foi repassada no período da colonização à novas regiões, cujas diversidades geográficas e climáticas proporcionam a uvas e vinhos concentrações variadas de compostos fenólicos, uma fonte de antioxidantes, capazes de redução e prevenção do risco de doenças. Este trabalho teve como objetivo verificar a existência de correlações entre composição fenólica e atividade antioxidante de vinhos tintos elaborados por quatro distintos países do hemisfério sul. A pesquisa foi constituída por dez amostras de vinhos tintos comerciais, a partir das variedades de uva, Cabernet Sauvignon (CS) e Syrah (SY), safra 2012, produzidos no Brasil (Vale do São Francisco (VSF) e do Rio Grande do Sul (RS)), no Chile, na Austrália e na África do Sul. Os vinhos foram avaliados por meio de análises, físico-químicas, espetrofotométricas e cromatográficas, com determinação e quantificação de compostos fenólicos, parâmetros cromáticos (intensidade de cor, tonalidade e % de vermelho, amarelo e azul) e capacidade antioxidante (% de inibição do DPPH*). As análises foram submetidas ao teste de variância (ANOVA), utilizando o teste de Duncan para comparação. Quanto as análises físico-quimicas clássicas, exceto o pH que apresentou valores elevados, todas as amostras estavam coerentes com os achados da literatura. Todos os vinhos estudados apresentaram elevada capacidade antioxidante (96,80- 95,01% (SY) e 97,47-94,0% (CS)) e valores elevados de polifenóis totais, com valores mínimo, 1421,5 e 1045,4 mg.L-1 e máximo, 1905,7 e 3052,72 mg.L-1 em equivalente de ácido gálico (EAG), exibidos por uvas do tipo SY e CS, respectivamente. Elevadas correlações foram verificadas entre a capacidade antioxidante e polifenóis totais em vinhos do Chile, Rio Grande do Sul e Vale do São Francisco, da uva Syrah, e da África, Chile e Vale do São Francisco, da Cabernet Sauvignon. O conteúdo de antocianina apresentou diferenças significativas entre todos os vinhos avaliados de ambos cultivares. Os resultados referentes à caracterização cromática foram elevados para todos os parâmetros, revelando os vinhos pesquisados como envelhecidos. Neste estudo, o isômero trans- resveratrol não foi detectado em nenhuma das amostras avaliadas, contudo, a concentração do isômero cis- detectada variou de 0, 00 a 0,32 mg.L-1 nos vinhos CS e 0,00 a 0,29 nos vinhos SY. Dentre os ácidos pesquisados, o gálico apresentou superioridade, porém foi não encontrada correlação do mesmo com a capacidade antioxidante. Estes resultados apontam para a influência do tipo de fenólico, presente nas variedades de uvas, sobre a capacidade antioxidante destes vinhos.<br>The wine industry, commonly practiced in European countries, was passed in the period of colonization of new regions, whose geographical and climatic diversity provide the grapes and wines varying concentrations of phenolic compounds, a source of antioxidants, able to reduce and prevent the risk of disease . This study aimed to verify the existence of correlations between phenolic composition and antioxidant activity of red wines produced by four different countries of the South. The survey consisted of ten samples of commercial red wines from the grape varieties Cabernet Sauvignon (CS) and Syrah (SY), vintage 2012, produced in Brazil (Vale do São Francisco (VSF) and Rio Grande do Sul (RS)), Chile, Australia and South Africa. The wines were evaluated through analysis, physicochemical, espetrofotométricas and chromatographic with determination and quantification of phenolic compounds, chromatic parameters (color intensity, tone and % red, yellow and blue) and antioxidant capacity (% inhibition of DPPH *). The analyzes were subjected to analysis of variance (ANOVA) using Duncan's test for comparison. As the classical physical-chemical analysis, except that showed high pH values, all samples were consistent with the literature findings. All studied wines showed high antioxidant capacity (96,80- 95,01% (SY) and from 97.47 to 94.0% (CS)) and high values of total polyphenols, with minimum, 1421.5 and 1045, 4 mg l-1 and maximum of 1905.7 and 3052.72 mg L-1 equivalent of gallic acid (EAG), displayed by grape type SY and CS respectively. High correlations were found between the antioxidant capacity and total polyphenols in wines from Chile, Rio Grande do Sul and São Francisco Valley, the Syrah grape, and Africa, Chile and Vale do São Francisco, the Cabernet Sauvignon. The anthocyanin content showed significant differences among all evaluated wines of both cultivars. The results of the chromatic characterization were high for all parameters, revealing the wine researched as aged. In this study, the isomer trans-resveratrol was not detected in any of the samples, however, the concentration of the cis isomer detected ranged from 0 00 to 0.32 mg.L-1 to CS wines and 0.00 to 0, 29 in SY wines. Among the surveyed acid, gallic presented superiority, but no correlation was found with the same antioxidant capacity. These results point to the influence of the type of phenolic, present in grape varieties on the antioxidant capacity of these wines.
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Pinto, Camila Ferreiro. "Avaliação do estado oxidante/antioxidante e da defesa eritrocitária antioxidante em felinos com linfoma." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-11012012-140805/.
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Os linfomas constituem um grupo de neoplasias que têm origem nas células linforreticulares e acomete tecidos linfóides primários, secundários como o baço e linfonodos e demais tecidos onde há presença de linfócitos circulantes, comumente descritos em cães, gatos e humanos. As síndromes paraneoplásicas são definidas como alterações sistêmicas não relacionadas com lesões metastáticas de forma direta ou indireta no hospedeiro. Dentre as alterações descritas como síndrome paraneoplásica, as alterações hematológicas constituem as mais freqüentes, apresentando destaque para os processos anêmicos. A anemia presente pode ser decorrente de alterações do metabolismo do ferro, perda sanguínea, distúrbios hemolíticos, infiltrado medular e hiperesplenismo. Atualmente tem se associado a redução da vida média das hemácias frente a presença do estresse oxidativo, que gera um desequilíbrio entre a excessiva produção de espécies reativas ao oxigênio e/ou a diminuição dos mecanismos de defesa antioxidante das hemácias. Esse processo pode ocasionar a peroxidação de lipídios da membrana eritrocitária, gerando hemólise e assim resultando em anemia e/ou exacerbando a mesma. Com o objetivo de avaliar a existência do estresse oxidativo e a presença de anemia assim como, a sua correlação com o estado redox, foram avaliadas as concentrações eritrocitárias de glutationa reduzida, glutationa redutase, glutationa peroxidase e superóxido redutase em 23 gatos sadios e 17 felinos com linfoma. Também foram determinadas as concentrações plasmáticas de malonaldeído como indicador da presença de peroxidação lipídica em ambos os grupos. Para avaliar o estado redox foi mensurada a concentração plasmática do estado antioxidante total para o grupo experimental e grupo controle. Não foram observadas diferenças significantes para as enzimas eritrocitárias glutationa redutase, glutationa peroxidade e superóxido dismutase, assim como para a mensuração plasmática de malonaldeído. Entretanto, foram observados valores significativamente menores (p=0,018) de glutationa reduzida nos felinos com linfoma quando comparados ao grupo controle. O mesmo pôde ser observado em relação à mensuração do estado antioxidante total (p=0,003). Os resultados obtidos indicam a presença de estresse oxidativo em felinos com linfoma, porém, não houve evidencias da relação entre a presença de estresse oxidativo e a presença de anemia.<br>Lymphomas are a group of cancers that originate in cells and lymphoreticular affects lymphoid tissues in primary, secondary as the spleen and lymph nodes and other tissues where there is presence of circulating lymphocytes, commonly described in dogs, cats and humans. Paraneoplastic syndromes are defined as systemic changes unrelated metastatic lesions either directly or indirectly in the host. Among the changes described as a paraneoplastic syndrome, hematological changes are the most frequent, with emphasis on the processes anemic. This anemia may be due to changes in iron metabolism, blood loss, hemolytic disorders, bone marrow infiltration and hypersplenism. Today has been associated with reduced average life span of red cells before the presence of oxidative stress, which creates an imbalance between excessive production of reactive oxygen species and / or decreased antioxidant defense mechanisms of red blood cells. This process can lead to lipid peroxidation of the membrane, causing hemolysis and thus resulting in anemia and / or exacerbating it. Aiming to evaluate the existence of oxidative stress and anemia as well as its correlation with redox state, were evaluated erythrocyte concentrations of reduced glutathione, glutathione reductase, glutathione peroxidase and superoxide reductase in 23 healthy cats and 17 cats with lymphoma. We also determined plasma concentrations of malondialdehyde as an indicator of the presence of lipid peroxidation in both groups. To assess the redox state was measured plasma concentration of total antioxidant status for the experimental group and control group. No significant differences were observed for enzymes erythrocyte glutathione reductase, glutathione peroxidase and superoxide dismutase, as well as for measurement of plasma malondialdehyde. However, observed values were significantly lower (p = 0.018) reduced glutathione in cats with lymphoma when compared to the control group. The same could be observed in relation to the measurement of total antioxidant status (p=0,003). The results indicate the presence of oxidative stress in cats with lymphoma, however, no evidence of the relationship between oxidative stress and anemia.
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Nascimento, Priscilla Marques do. "Metabolismo oxidativo e perfil bioquímico de ovelhas Santa Inês no período periparto: efeito da suplementação com vitamina E." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-12082014-133356/.
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Para avaliar o metabolismo oxidativo, perfil bioquímico e o efeito da suplementação com vitamina E intramuscular no período periparto, foram utilizadas 24 ovelhas, hígidas, da raça Santa Inês, no último mês de gestação. As ovelhas foram distribuídas em dois grupos que receberam, com intervalo de 14 dias, duas aplicações pela via intramuscular profunda de 2 mL de solução fisiológica (grupo controle-GC), ou 200 UI de vitamina E (grupo tratado-GT). Estes grupos foram subdivididos em P1 e P2. No P1, as ovelhas receberam a segunda dose de solução fisiológica ou vitamina entre 1 e 7 dias da data do parto. No P2, a segunda dose foi administrada entre 15 e 25 dias da data do parto. As amostras de sangue foram coletadas nos seguintes momentos: previamente à primeira aplicação (M0), 15 dias após a primeira aplicação (M1), no momento do parto (M2), 7 dias após o parto (M3), duas semanas após o parto (M4) e 4 semanas após o parto (M5). Foram analisadas as variáveis do perfil bioquímico: proteína total, albumina, globulina, uréia, creatinina, creatinofosfoquinase (cK), ácido úrico, aspartatoaminotransferase (AST), gamaglutamiltransferase (GGT), colesterol, triglicérides, glicose, beta hidroxibutirato (BHB) , ácidos graxos não esterificados (NEFA). Do metabolismo oxidativo foram determinas as atividades da superóxido dismutase (SOD), glutationa peroxidase (GSH-Px), glutationa reduzida (GSH) e habilidade de redução férrica plasmática (HRFP). Em P1, não foram observadas diferenças entre os grupos tratado e controle nas concentrações de proteína total, globulina, cK, ácido úrico, glicose, triglicérides, BHB, NEFA, SOD, GSH-Px e GSH. Porém em P1, foram observadas maiores concentrações em de albumina em M0 (P=0,039); uréia em M1 (P=0,018), M2 (P=0,005) e M3 (P=0,040); a creatinina em M2 (P=0,030) e M3 (P=0,047); GGT em M1 (P= 0,01) e M2 (P=0,024); colesterol em M2 (P=0,041) e HRFP em M3 (P= 0,022) para as ovelhas tratadas em relação às controle. Em P1, a AST foi maior para o controle em relação ao tratado em M2 (P=0,030). Em P2, foram observadas maiores atividades para o grupo controle nas variáveis SOD em M3 (P=0,013) e GSH-Px em M4 (P=0,027) e maior HRFP em M4 (P=0,023) para o grupo tratado. A aplicação de duas doses de vitamina E (200 UI, via IM) aumentou as concentrações de HRFP no pós-parto tanto em P1 como em P2.<br>Oxidative metabolism, biochemical profile and the effect of intramuscular vitamin E supplementation on sheeps per partum period were evaluated using 24 healthy Santa Ines sheep, in the last month of pregnancy. The lambs were randomly divided into two groups, control group-CG and treated group-TG. CG received 2 mL of saline and TG received 200 IU of vitamin E, both treatments were done with two doses within interval of 14 days, by deep intramuscular injection of. These groups were further divided into P1 and P2. In P1 the sheep received the second or vitamin saline dose between 1 and 7 days before delivery date. In P2, the second dose was administered between 15 and 25 days before delivery. Blood samples were collected at the following times: before the first application (M0), 15 days after (M1), at birth (M2), 7 days postpartum (M3), two weeks after delivery (M4) and four weeks after delivery (M5). The variables of biochemical profile analyzed were: total protein, albumin, globulin, urea, creatinine, creatine kinase (CK), uric acid, aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), cholesterol, triglycerides, glucose, beta hydroxybutyrate (BHB), acids non-esterified fatty acids (NEFA). Oxidative metabolism variable were: activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), reduced glutathione (GSH) and ferric reducing ability of plasma (HRFP). No differences were observed between the P1 treated and control groups in the concentrations of total protein, globulin, CK, uric acid, glucose, triglycerides, BHB, NEFA, SOD, GSH-Px and GSH. However higher concentrations of albumin in M0 (P = 0.039), urea in M1 (P = 0.018), M2 (P = 0.005) and M3 (P = 0.040), creatinine in M2 (P = 0.030 ) and M3 (P = 0.047), GGT in M1 (P = 0.01) and M2 (P = 0.024), cholesterol in M2 (P = 0.041) and HRFP at M3 (P = 0.022) for ewes treated we observed. AST concentration was greater for control in M2 (P = 0.030). In P2, higher activities were observed for the control group in the variables SOD in M3 (P = 0.013), GSH-Px in M4 (P = 0.027) and higher FRAP in M4 (P = 0.023) for the treated group. The application of two doses of vitamin E (200 IU, im) increased the concentrations of FRAP postpartum in both P1 and P2.
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Yamamoto, Fernando Yugo. "Determinação da exigência de vitamina E para o dourado Salminus brasiliensis (Cuvier, 1816) e a avaliação do seu efeito imunomodulador." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-04052015-172634/.
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Agentes estressores em piscicultura intensiva afetam a condição fisiológica e o sistema imune dos peixes aumentando a susceptibilidade a infecções e causando prejuízos econômicos. Para contornar este problema, o uso de nutrientes moduladores do sistema imunológico na dieta, como o tocoferol, se tornam estratégia profilática para as pisciculturas assegurarem uma maior sobrevivência e consequente produtividade. O presente estudo visou avaliar a exigência nutricional do dourado, Salminus brasiliensis, por meio de um ensaio dose-resposta e aferir seu efeito imunomodulador. O delineamento utilizado foi o inteiramente casualizado, com sete tratamentos/dietas semi purificadas elaboradas com doses crescentes de vitamina E (0; 50; 100; 150; 200, 250 e 3500 mg kg-1α-tocoferol acetato) (n=4). Quinze juvenis de dourado foram alojados em caixas de polipropileno, em sistema de recirculação fechado com filtragem mecânica e biológica, trocador de calor com termostato e aeração forçada através de sopradores e pedras difusoras. Após serem alimentados por 30 dias com a dieta basal para depleção de vitamina E nas reservas corporais de vitamina, os animais foram pesados (20,04 ± 0,09 g), redistribuídos em 28 tanques (500 L; 15 peixes por tanque) e alimentados durante 78 dias até saciedade aparente (duas refeições diárias: 08h00m e 17h00m). Os peixes apresentaram diferença no ganho de peso, porém não de maneira dependente do tratamento de vitamina E. Após o período de alimentação os peixes foram desafiados com a bactéria Aeromonas hydrophila. Os parâmetros imunológicos foram aferidos antes e após o desafio e não houveram diferenças significativas para: atividade respiratória dos leucócitos, atividade da lisozima sérica, proteína e albumina total no soro e sobrevivência. Houve aumento da concentração das globulinas totais no soro após infecção em função do nível de vitamina E na dieta, e a dose ótima foi definida por meio da regressão segmentada: 151,07 mg kg-1 de vitamina E na ração. A exigência de vitamina E para o dourado foi determinada em 58,90 mg kg-1 pelas substâncias reativas ao ácido tiobarbiturico da fração mitocondrial do fígado por análise de regressão segmentada.<br>Stressors in intensive fish farming affect fish physiological conditions and immune system, promoting susceptibility to infections and causing economic losses. To overcome this issue, using immunomodulatory nutrients such as tocopherol on fish feeds may become a prophylactic strategy to fish farms to ensure a higher survival and productivity. The present study aimed at determining vitamin E requirement of dourado, Salminus brasiliensis, through a dose dependent trial and how the immune system responded to vitamin E crescent doses. The experiment design was randomly distributed in seven treatments (n=4) of semi purified diets (0; 50; 100; 150; 200; 250 and 3,500 mg kg-1). After exposing the fish during 30 days for tocopherol depletion, fifteen dourado juveniles (20.04 ± 0.09 g) were stocked in 500 L tanks in a closed loop system and fed twice a day until apparent satiation. Differences in weight gain were observed however not in a vitamin E dose dependent way. After feeding for 78 days fish were challenged with intraperitoneal bacterial infection (Aeromonas hydrophila). Immunological parameters were measured before and after infection and no significant differences were observed in: blood leukocyte burst respiratory activity, serum lysozyme activity, serum protein and albumin, and survival. However a higher total serum globulin was detected after infection and the best response determined through a broken-line regression was 151.07 mg kg-1 of vitamin E on fish feed. Dietary requirement of vitamin E was determined by broken-line regression from thiobarbituric reactive substances of liver mithocondrial fraction to be 58.90 mg/kg of α-tocopherol acetate.