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Rix, Catherine S. "Detecting life on Mars and the life marker chip : antibody assays for detecting organic molecules in liquid extracts of Martian samples". Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/7250.
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The Life Marker Chip instrument, which has been selected to fly as part of the 2018 ExoMars rover mission payload, aims to detect up to 25 organic molecules in martian rocks and regolith, as markers of extant life, extinct life, meteoritic in-fall and spacecraft contamination. Martian samples will be extracted with a solvent and the resulting liquid extracts will be analysed using multiplexed microarray-format immunoassays. The LMC is under development by an international consortium led by the University of Leicester and the work described within this thesis was carried out at Cranfield University as part of the consortium’s broader program of work preparing the LMC instrument for flight in 2018. Within this thesis four specific areas of LMC instrument development are addressed: the investigation of immunoassay compatible liquid extraction solvents, the study of likely interactions of martian sample matrix with immunoassays, the development of antibodies for the detection of markers of extinct life and demonstration of solvent extraction and immunoassay detection in a flight representative format. Cont/d.
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Palu, Doreen. "Etude de la composition chimique d’extraits d’Ilex aquifolium Linné et de Calicotome villosa (Poiret) Link de Corse par RMN du carbone-13". Electronic Thesis or Diss., Corte, 2022. http://www.theses.fr/2022CORT0018.
Streszczenie:
L’objectif de ce travail de thèse était de déterminer la composition chimique d’extraits de plantes de Corse encore peu ou pas étudiées et susceptibles d’avoir des activités biologiques valorisables. Cette étude a été menée en mettant en œuvre la méthodologie d’analyse des mélanges complexes par RMN 13C, développée depuis une trentaine d’années par l’équipe « Chimie et Biomasse » de l’UMR CNRS 6134 Sciences pour l’Environnement de l’université de Corse. Dans une première partie, nous avons étudié la composition chimique d’extraits de houx commun (Ilex aquifolium L.). Deux extraits de feuilles (obtenus à l’hexane et au dichlorométhane) ont chacun subi deux fractionnements successifs par chromatographie sur colonne ouverte de silice. L’analyse par RMN 13C (CPG(Ir) et CPG-SM également dans certains cas) des extraits bruts et des fractions de chromatographie a permis l’identification de onze triterpènes dont l’α-amyrine et la β-amyrine et certains de leurs esters. Parallèlement, deux acides triterpéniques d’intérêt (acide ursolique et acide oléanolique) ont été quantifiés par RMN 1H au sein de l’extrait brut au dichlorométhane via une méthode rapide mise au point et validée (justesse, linéarité, précision des mesures). Ces deux composés représentent respectivement 55,3% et 20,8% de l’extrait. Nous avons également réalisé, en collaboration avec l’équipe « Biochimie et Biologie Moléculaire du Végétal » de l’université de Corse, des tests antimicrobiens sur les extraits et certaines fractions de chromatographie. Les deux acides triterpéniques précédemment cités ont montré une activité antimicrobienne comparable à celle du chloramphénicol (antibiotique de référence) vis-à-vis de trois bactéries à Gram positif, Staphylococcus aureus, Staphylococcus epidermidis et Bacillus cereus (CMI = 4 et 8 mg.L-1 vs. 2 et 4 mg.L-1). Par ailleurs, nous avons préparé des extraits de baies de houx en utilisant différents solvants : hexane, dichlorométhane, dichlorométhane/acétate d’éthyle (50/50, v/v). Les deux derniers extraits (dichlorométhane et dichlorométhane/acétate d’éthyle) ont subi des fractionnements successifs et l’étude des spectres RMN 13C des extraits bruts et des fractions de chromatographie a permis d’identifier neuf triterpènes (précédemment identifiés), cinq dérivés phénoliques, six monosaccharides ainsi que quatre lactones (la ménisdaurilide, l’aquilégiolide, la 7-épi-griffonilide et la dasycarponilide) non encore répertoriées dans le houx commun. Dans une seconde partie, nous avons étudié la composition chimique d’extraits de fleurs et de racine de Calicotome villosa (Poir.) Link. Les extraits de fleurs obtenus au dichlorométhane et à l’acétate d’éthyle ont été soumis à des chromatographies successives. L’analyse par RMN 13C des extraits bruts et des fractions de chromatographie a permis l’identification de trois flavonoïdes, cinq dérivés glucosylés de flavonoïdes et quatre phénylpropanoïdes. Dans cette partie, nous nous sommes également intéressés à la composition chimique d’un extrait méthanolique de racine de C. villosa qui n’a fait l’objet d’aucune étude de ce type au préalable. Cet extrait a été soumis à plusieurs fractionnements successifs et dix-huit composés, notamment des stérols, des flavonoïdes, un polyphénol et des ptérocarpanes ont été identifiés par RMN 13CThe aim of this work was to determine chemical composition of wild growing corsican understudied plant species, with potential biological activities. This study was realized using the computerized NMR method developed over the past thirty years by the University of Corsica “Chimie et Biomasse” group, UMR CNRS “Sciences Pour l’environnement”. Identified secondary metabolites were then undertaken to evaluate their antimicrobial properties. As part of this study, we selected on the first place commun holly (Ilex aquifolium L.). After two successive column chromatography, hexane and dichloromethane leaves crude extracts and all chromatography fractions were analyzed by 13C NMR (GC(RI) and GC-MS sometimes) to allow the identification of eleven triterpens and α- and β-amyrin esters. Among identified compounds, ursolic acid and oleanolic acid were also quantified by 1H NMR in the dichloromethane crude extract using a reliable method developped and validated (accuracy, linearity precision of measurements). Ursolic acid accounted for 55.3% of the extract, followed by oleanolic acid, 20.8%. Evaluation of previous identified compounds antimicrobial activities has been performed in collaboration with « Biochimie et Biologie Moléculaire du Végétal » group (University of Corsica). Triterpen acids and chloramphenicol (reference antibiotic) displayed similar antibacterial activities against three Gram-positive bacteria, Staphylococcus aureus, Staphylococcus epidermidis and Bacillus cereus (MIC = 4 and 8 mg.L-1 vs. 2 and 4 mg.L-1). Moreover, dichloromethane and dichloromethane/ethyl acetate (50/50, v/v) berries extracts were submitted to successive column chromatography. Crude extracts and chromatography fractions 13C NMR spectra revealed presence of nine triterpens previously identidied, five phenolics derivatives, six monosaccharides and four lactones (menisdaurilide, aquilegiolide, dasycarponilide and 7-epi-griffonilide) were first time identified in berries holly extracts. On the second place, we determined chemical compositions of Calicotome villosa (Poir.) Link flowers and root extracts. 13C NMR analysis of dichloromethane and ethyl acetate flowers extracts and their chromatography fractions, allowed the identification of three flavonoids, five glycosyl flavonoids and four phenylpropanoids. We also studied chemical composition of a methanol root extract which has never been submitted to any chemical composition study. After successive column chromatography, eighteen compounds were identified by 13C NMR including sterols, flavonoids, a polyphenol and pterocarpans
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Coppa, Carolina Fernanda Sengling Cebin. "Extração de oleuropeína de folhas de oliva com solvente hidroalcoólico e efeito dos extratos sobre a estabilidade oxidativa de óleos vegetais". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-01062016-114325/.
Streszczenie:
A oleuropeína é o composto fenólico mais abundante presente nas folhas da oliveira, sendo que muitos estudos vêm demonstrando que este composto apresenta importantes propriedades antimicrobiana, antioxidante, anti-inflamatória, entre outras, surgindo o interesse em estudos de métodos para sua extração e aplicação em produtos na área alimentícia, cosmética e farmacêutica. O objetivo deste estudo foi a extração da oleuropeína à partir de folhas de oliva, utilizando solvente não tóxico, para posterior aplicação dos extratos em óleos vegetais a fim de se verificar seu efeito sobre a estabilidade oxidativa dos mesmos. O solvente selecionado para o estudo foi uma mistura de etanol e água (70:30, em massa, condição obtida através de um trabalho prévio), na presença de 1 % de ácido acético. Em uma primeira etapa, foram realizados experimentos de extração utilizando-se as técnicas de maceração (tipo I) e ultrassom (tipo II), em diferentes condições de temperatura (20, 30, 40, 50 e 60°C). Em uma segunda etapa, através de experimentos com maceração à temperatura ambiente, estudou-se o efeito da razão folhas:solvente (1:8, 1:6 e 1:3) e a influência da presença de ácido acético sobre o processo de extração (tipo III). Por fim, realizando-se a maceração na presença de ácido acético, temperatura ambiente e proporção folhas: solvente igual a 1:3, realizaram-se extrações sequenciadas a partir de uma mesma matéria-prima (tipo IV). Os resultados desses experimentos foram expressos em rendimento de oleuropeína (RO), teor de oleuropeína nos extratos (TO) e rendimento global (RG). Analisando-se os experimentos I e II, verificou-se que a temperatura não exerceu influência significativa sobre as respostas RO, TO e RG. Além disso, verificou-se que os valores das respostas para os experimentos com a maceração foram um pouco maiores do que os valores obtidos para as extrações com o auxílio do ultrassom. Nos experimentos tipo III, em linhas gerais, observou-se a influência positiva da presença do ácido acético sobre as respostas estudadas. Verificou-se também que, na presença de ácido, o aumento da quantidade de solvente na extração conduz ao aumento de RO e RG, e à diminuição de TO. Através do experimento tipo IV, constatou-se que mesmo após quatro extrações sequenciadas, ainda não foi possível esgotar a oleuropeína da matéria-prima. Após a obtenção de todos os extratos hidroalcoólicos, selecionou-se um contendo aproximadamente 19 % de oleuropeína para o estudo da estabilidade oxidativa em óleos vegetais (oliva e girassol) utilizando o método Rancimat. A presença de extrato aumentou em 3 horas o tempo de indução do azeite de oliva extra-virgem, e em 2 horas o tempo de indução do azeite de oliva comum. Os óleos de girassol bruto e refinado não apresentaram melhora na estabilidade oxidativa quando adicionados dos extratos. Foram realizados também testes de estabilidade oxidativa através da adição direta de folhas de oliva em pó nos azeites de oliva extra-virgem e comum. Para o azeite extra-virgem, a adição das folhas não proporcionou melhora da estabilidade oxidativa, porém para o azeite comum, houve um aumento de mais de 2 horas no tempo de indução.Os resultados apresentados neste trabalho demonstraram que é possível obter extratos contendo teores significativos de oleuropeína utilizando-se um solvente renovável. Além disso, constatou-se que os mesmos podem ser utilizados como um antioxidante natural em azeite de oliva, melhorando sua estabilidade oxidativa.Oleuropein is the most abundant phenolic compound present in the leaves of the olive tree, and many studies have shown that this compound has significant antimicrobial properties, antioxidant, anti-inflammatory, among others, emerging interest in studies of methods for extraction and use in products in the food industry, cosmetics and pharmaceuticals. The aim of this study was the extraction of oleuropein from the olive leaf, using non-toxic solvent, for further application of the extracts in vegetable oils in order to check its effect on their oxidative stability. The solvent selected for the study was a mixture of ethanol and water (70:30, % mass, condition obtained from a previous study), in the presence of 1 % acetic acid. In a first step, extraction experiments were conducted using maceration (type I) and ultrasound (type II) under different temperature conditions (20, 30, 40, 50 and 60 ° C). In a second step, through experiments with maceration at room temperature, the effect of the ratio olive leaves:solvent (1:8, 1:6 and 1:3) and the influence of the presence of acetic acid on the process of extraction (type III) was studied. Finally, using maceration in the presence of acetic acid at room temperature and proportion olive leaves:solvent of 1:3, sequencial extractions from the same raw material (type IV) were performed. The results of these experiments were expressed in oleuropein yield (RO), oleuropein content in extracts (TO) and global yield (RG). Analyzing the experiments I and II, it was found that the temperature did not have significant influence on the RO, TO and RG values. Furthermore, it was found the response values for the experiments with maceration was somewhat higher than values obtained for extractions using ultrasound. In type III trials, in general, a positive influence of the presence of acetic acid in the studied answers were observed. It was also found that in the presence of acid, higher amount of solvent leads to an increase of RO and RG values, and a decrease of TO value. Through the experiment type IV, it was found that even after four sequential extractions, it was not possible to exhaust oleuropein raw material. After obtaining all the hydroalcoholic extracts, na extract contanining approximately 19 % of oleuropein was selected for the study of oxidative stability of vegetable oils (olive and sunflower oil), using the Rancimat method. The presence of extract increased in 3 hours the induction time of extra-virgin olive oil, and in 2 hours the induction time of common olive oil. Crude and refined sunflower oils showed no improvement in the oxidative stability when added to the extracts. Oxidative stability tests were also performed by direct addition of olive leaf powder in extra virgin and common olive oil. For extra virgin olive oil, the addition of the powder leaves did not improve the oxidative stability, but for the common oil, an increase of more than 2 hours in induction time was observed. Results demonstrated that it is possible to obtain extracts containing significant concentrations of oleuropein using a renewable solvent. Furthermore, it was found that it can be used as a natural antioxidant in olive oil, improving its oxidative stability.
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Tófoli, Rodolfo José [UNESP]. "Avaliação de biocompostos e composição mineral de extratos provenientes de duas macroalgas lóticas do estado de São Paulo". Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/150494.
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No Brasil, há uma grande biodiversidade de espécies de algas lóticas, Dentre as mais conhecida, encontradas em rios e riachos da região sudeste do estado de São Paulo destaca-se a Oedogonium sp. e a Nitella microcarpa var. wrightii., dois gêneros de algas verdes. Entretanto, estudos de caracterização química de extratos destas algas ainda são inexistentes. Por esse motivo destaca-se a importância deste trabalho, o qual encontra-se subdivido em dois estudos. O primeiro teve por objetivo avaliar e quantificar compostos fenólicos e capacidade antioxidade de extratos de diferentes solventes da alga Oedogonium sp. Utilizou-se um delineamento experimental de mistura para determinar a influência dos solventes e verificou-se qual desses apresentou melhor rendimento na extração desses compostos da alga em pó. O segundo estudo teve por objetivo realizar a caracterização de duas macroalgas verdes: Nitella microcarpa var. wrightii, e Oedogonium sp., através da obtenção de um extrato, com o melhor sistema de solventes obtidos no primeiro estudo. Desta forma, foi possível quantificar quanto a presença de minerais, flavonoides, umidade, carotenoides, compostos fenólicos e capacidade antioxidante. No primeiro estudo, os resultados sugeriram que a mistura acetona-etanol apresentou melhor rendimento de extração tanto para compostos fenólicos como à capacidade antioxidante. No segundo estudo, a alga Oedogonium sp. destacou-se por apresentar uma grande quantidade de carotenoides totais. Já a espécie Nitella microcarpa var. wrightii, obteve altos valores de minerais.
In Brazil, there is a great biodiversity of lotic algae species. Among the most well known species found in rivers and streams in the southeast region of the state of São Paulo is Oedogonium sp. and Nitella microcarpa var. Wrightii., Two genus of green algae. However, studies of chemical characterization of extracts of these algae are still non existent. For this reason the importance of this work is highlighted, which is subdivided in two studies. The first one had the objective to evaluate and quantify phenolic compounds and antioxidant capacity of extracts of different solvents of the algae Oedogonium sp. An experimental design of the mixture was used to determine the influence of the solvents and it was verified which of them presented better yield in the extraction of these compounds from the powdered seaweed. The second study aimed to characterize two green macroalgae: Nitella microcarpa var. Wrightii, and Oedogonium sp., by obtaining an extract, with the best solvent system obtained in the first study. In this way, it was possible to quantify the presence of minerals, flavonoids, moisture, carotenoids, phenolic compounds and antioxidant capacity. In the first study, the results suggested that the acetone-ethanol-water mixture had a better extraction yield for both phenolic compounds and antioxidant capacity. In the second study, the alga Oedogonium sp. was characterized by a large amount of total carotenoids. The other alga, of the species Nitella microcarpa var. Wrightii, has achieved high mineral values.
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Ceschini, Valmir Carneiro. "Potencial antífungico de extratos de folhas de Eucalyptus staigeriana F. Muell. sobre Aspergillus flavus". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-22112011-135925/.
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O objetivo deste trabalho foi avaliar o potencial antifúngico contra o fungo Aspergillus flavus, dos extratos de folhas de Eucalyptus staigeriana F. Muell., preparados a partir de folhas frescas, liofilizadas e secas ao ambiente, sob diferentes tempos de extração e por diferentes solventes extratores, tais como metanol, etanol e água a temperatura ambiente e água a 60ºC. Para mensurar o potencial antifúngico foi utilizada a técnica de poisoned food em meio BDA e o crescimento radial fúngico foi avaliado por seis dias. O percentual de inibição foi avaliado comparando-se as medidas do diâmetro radial de crescimento fúngico dos extratos com as placas controle contendo apenas os solventes. Como controle positivo foi utilizado o óleo essencial de E. staigeriana. Os extratos metanólicos apresentaram o melhor potencial antifúngico, seguido pelos extratos etanólicos e aquosos. A utilização das folhas frescas mostrou-se a melhor forma de preparação e não houve diferença significativa entre os tempos de extração 1h e 24h, indicando como processamento mais viável a extração em 1h. A Concentração Inibitória Mínima (MIC) foi mensurada para o extrato de melhor desempenho pela técnica de micropoços, aonde o crescimento fúngico foi monitorado por fluorescência derivada da reação da esterase fúngica com o diacetado de fluorescina. E o extrato que obteve o melhor resultado foi o extrato metanólico, com 1h de extração, a partir de folhas liofilizadas de E. staigeriana, e sua MIC foi de 26,75 L/mL, enquanto a do seu óleo essencial foi de 12,5 L/mL, demonstrando a eficiência relativa da extração com solventes extratores e sua praticidade e operacionalidade, quando se comparam com a extração de óleos essenciais.This study aimed to evaluate the antifungal potential of Eucalyptus staigeriana F. Muell. leaf extracts against Aspergillus flavus. The extracts were prepared using fresh, lyophilized, and air-dried leaves, different extraction times, and different solvents, such as methanol, ethanol, water at room temperature, and water at 60ºC. To measure the antifungal potential, the poisoned food technique was used in PDA medium, and the radial growth of the fungus was evaluated for six days. The percentage of inhibition was assessed by comparing the measurements of the radial growth diameter of the fungus in the extracts with the control plates containing only the solvents. The essential oil of E. staigeriana was used as a positive control. The methanolic extracts presented the best antifungal potential, followed by the ethanolic and aqueous extracts. The use of fresh leaves was the best type of preparation and no statistically significant difference between 1-h and 24-h solvent extraction was found, indicating the 1-h extraction process as the most feasible. The extract presenting the best performance using the microwell technique had the minimum inhibitory concentration (MIC) measured, and the fungal growth was monitored by fluorescence derived from the fungal esterase reaction with fluorescein diacetate. The extract that achieved the best result the methanolic extract, with 1-h extraction from lyophilized leaves of E. staigeriana, and the MIC was 26.75 L/mL, while the essential oil was 12.5 L/mL, demonstrating the relative efficiency of the solvent extraction and its practicality and easy implementation when compared with the extraction of essential oils.
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Gomes, Anabele Stefânia. "Atividade fitotóxica de extratos foliares de Pouteria torta (Mart.) Radlk". reponame:Repositório Institucional da UnB, 2013. http://repositorio.unb.br/handle/10482/14735.
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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Botânica, Programa de Pós-Graduação em Botânica, 2013.Submitted by Alaíde Gonçalves dos Santos (alaide@unb.br) on 2013-11-27T14:34:04Z No. of bitstreams: 1 2012_AnabeleStefaniaGomes.pdf: 1370930 bytes, checksum: 4d5d493106f69e8466f2278a7446d488 (MD5)
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Muitos metabólitos secundários podem ser sintetizados desde os primeiros estágios da planta, no entanto outros podem ter sua produção desencadeada ou aumentada em resposta a algum estímulo ambiental, o que pode afetar seu potencial fitotóxico. O método de extração e o tipo de solvente utilizado para tal podem interferir na estrutura de produtos e na quantidade a ser extraída. O objetivo desse trabalho foi avaliar o potencial fitotóxico de extratos aquosos de folhas de P. torta coletadas na estação chuvosa e na estação seca no Cerrado, e obtidos por extração a quente e a frio, nas espécies alvo Sesamum indicum (gergelim) e Urochloa decumbens (braquiária). Ainda, comparar a atividade dos extratos aquosos com extratos obtidos por acetato de etila. Os extratos foram testados em cinco concentrações, 200, 400, 800, 1600 e 3200 ppm. Foram realizados experimentos de germinação e crescimento inicial em placa de petri que foram mantidas em câmara de germinação por sete dias, a 30ºC, com fotoperíodo de 12h. Não houve diferença na atividade em relação à época de coleta ou ao método de extração. Em relação ao extrato obtido por acetato de etila, a extração aquosa mostrou-se mais indicada para obtenção de fitoquímicos na espécie estudada, por ter maior efeito inibitório sob as espécies-alvo, além de ter baixo custo. A germinabilidade e o tempo médio de germinação não foram alterados em nenhuma das espécies, no entanto, o crescimento inicial foi inibido. O crescimento radicular foi mais sensível aos efeitos dos fitoquímicos que o crescimento aéreo. O gergelim mostrou-se mais sensível aos tratamentos do que a braquiária. ______________________________________________________________________________________ ABSTRACT
Many secondary metabolites can be synthesized since the earliest stages of plants life, however, others may have their production initiated or increased in response to an environmental stress, which can affect their phytotoxic potential. The method of extraction and the solvent used may interfere with the structure of products and quantity to be extracted. The aim of this study is to evaluate phytotoxic potential of aqueous extracts from leaves of P. Torta, collected during the rainy and the dry season in Cerrado, obtained by hot and cold extractions, using as the target species Sesamum indicum and Urochloa decumbens. Also, to compare the activity of aqueous extracts with the extracts obtained by ethyl acetate. The extracts were tested at five different concentrations: 200, 400, 800, 1600 and 3200 ppm. Germination and early growth experiments were tested in Petri dish, which were kept in growth chamber for seven days, at 30°C, with a 12h photoperiod .There was no difference in the activity concerning to time of collection or method of extraction. Regarding the extract obtained by ethyl acetate, the aqueous extraction was more suitable for obtaining phytochemicals from the studied specie, because of greater inhibitory effect on target species and low cost. Germinability and the mean time to germination were not altered in any target species, however, early growth was inhibited. Root growth was more sensitive to effects of phytochemical than to aerial growth. The sesame was more sensitive to the treatments than brachiaria.
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Zamil, Raya. "Recycling Cathode of Lithium-Ion Battery by Using Deep Eutectic Solvents to Extract Cobalt". Thesis, Umeå universitet, Kemiska institutionen, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-173089.
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Zancan, Kelly Cristine. "Obtenção de extrato de gengibre (Zingiber officinale Roscoe) com dioxido de carbono supercritico e co-solventes : um estudo da atividade biologica dos extratos". [s.n.], 2001. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254874.
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Orientador: Maria Angela de Almeida MeirelesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: o gengibre e seus produtos tais como o óleo essencial e oleoresina são internacionalmente comercializados para uso nas indústrias de alimentose farmacêuticas.O óleo essencial possui os compostos mais voláteis responsáveis pelo aroma característico do gengibre e a oleoresina contem além destes, substâncias classificadas como pungentes. Algumas destas substâncias pungentes agem como importantes antioxidantes. Atualmente, antioxidante obtidos a partir de fontes naturais são associados a benefícios para saúde humana, uma vez que os radicais livres estão relacionados com doenças do coração, malária, AIDS, câncer, neurodegenerativas entre outras. Devido a isso toma-se muito importante o estudo de novos antioxidantes. O uso da extração supercritica tem crescido muito nos últimos anos, entretanto ainda é necessária a obtenção de um número considerável de informações experimentais para que a construção de plantas indústriais deste tipo de processo aconteça. Neste trabalho os efeitos da temperatura (25 e 35°C), pressão (200 e 250 bar) e o uso de co-solventes (etanol e isopropanol, ambos ai, 17% (mim)) sobre o rendimento total e a cinética de extração da oleoresina de gengibre foram estudados. O equipamento utilizado consistiu de um extrator de leito fixo com diâmetro de 2,83x10.2m e comprimento de 0,375 m. Os ensaios foram realizados com vazão média de CO2de 5,83xlO-5kg/s. Os experimentos tiveram 7 horas de duração. A duração do periodo de taxa constante de extração variou de 1,3 a 2,7 horas e os rendimentos ficaram na faixa de 1,93% a 2,65%. A identificação das substâncias presentes na oleoresina foi feita através de CGIEM. Os extratos de gengibre analisados mostraram-se antioxidantes eficazes, possuíram ação anticancerígenas para algumas linhagens de câncer e inibiram o crescimento de algumas bactérias aqui estudadas. A espectrofotometria mostrou-se inadequada para a quantificação dos gingeróis e shogaóis. Os extratos do período de taxa constante e de taxa decrescente de extração apresentaram monoterpenos, sesquiterpenos, gingeróis e shogaóis em sua composição, enquanto o período difusional mostrou principalmente gingeróis e shogaóis.
Abstract: Ginger and ginger products such as essencial oil and oleoresin are internationally comercialized for use in food and pharmaceutical processing. The essential oil posses the volatile compounds responsible for the characterist ginger flavor and the oleoresin contains also substances classified as pungent. Some of these pungent substances act as important antioxidant agents. Today, antioxidants from natural resources are associated with health benefits since oxygenated compounds are related to a positive action against heart deseases, malaria, neurodegenerative, AIDS, cancer. The use od SCFE in the last years has increased steadily but yet a number of experimental information needed for process desing is still lacking. In this work the effects of temperature ( 25 and 35°C), pressure (200 e 250 bar), and the use of co-colvent (ethanol and isopropanol, both at 1,17% (mim)) on the total yield (mass of oleoresin! mass of feed) and the kinetics of ginger oleoresin extraction studied. The experimental setup used has a fixed bed extractor wiyh a diameter2,83xl0.2 m and length of 0,375 m. The assays were done at a CO2 flow rate of 5,23xlO-5kg/s. Typical experimental runs took 7 hours. The duration of the constant extraction rate period ranged from 1,3 to 2,7 hours and the yields varied from 1,93 to 2,65%. The identification of the substances presents in the extracts was done by GC/MS. The extracts analised showed a power antioxidants. They also had a action against some kinds of cancer and some bacterias here studied. Spectrofotometry showed not adequated for gingerol and shogaol quantification. The extracts of the constant rate extration period and the decrescent rate extraction period presented of monoterpens, sesquiterpens, gingerols and shogaols in their composition while the extracts of difusion period showed mainly gingerols and shogaols.
Mestrado
Mestre em Engenharia de Alimentos
9
Veggi, Priscilla Carvalho. "Obtenção de extratos vegetais por diferentes metodos de extração : estudo experimental e simulação dos processos". [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254860.
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Orientador: M. Angela de A. MeirelesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Neste trabalho é apresentado um estudo comparativo do custo de manufatura para diferentes técnicas de extração: extração com solventes a baixa pressão (LPSE: Low Pressure Solvent Extraction) em taque agitado e percolação, e extração supercrítica (SFE: Supercritical Fluid Extraction). As estimativas dos custos para os processos de extração LPSE por agitação e percolação foram realizadas por meio do simulador de processos SuperPro DesignerÒ. Foi realizado um estudo experimental para a obtenção, por extração supercrítica, de polifenóis de folhas de pitanga (Eugenia uniflora). Para o estudo do aumento de escala, assumiu-se que os parâmetros em escala laboratorial: rendimento da extração, tempo e a relação entre a massa de alimentação e solvente, são mantidos constantes para o equipamento em escala industrial. Assim, as estimativas foram realizadas tendo como base dados de literatura para a matriz vegetal macela (Achyrocline satureioides). Os estudos foram realizados para extratores de 50 L, 100 L e 300 L. Os custos de manufatura para LPSE em taque agitado e percolação foram: US$ 877,21/kg; US$ 698,73/kg; US$ 573,34/kg e US$ 814,46/kg; US$ 567,86/kg; US$ 384,00/kg, respectivamente em extratores de 50 L, 100 L e 300 L. Notou-se a influência dos parâmetros tempo e rendimento no custo dos extratos. Posteriormente, um estudo do custo do extrato através do processo SFE para mesma matriz vegetal foi realizado. Porém, para SFE o custo do extrato foi estimado através do parâmetro tCER, tempo em que aproximadamente 70 % do leito de extração é esgotado, sendo esta uma boa estimativa para o menor tempo de ciclo. O custo de manufatura do extrato obtido por SFE foi US$ 585,49/kg. Uma avaliação comparativa entre os três processos foi realizada e, dentre os principais custos obtidos: de investimento inicial, matéria-prima e utilidades, notou-se que o custo de investimento não é predominante na formação do custo de manufatura. O custo de matéria-prima para alguns dos tamanhos de extratores representou o fator preponderante. Posteriormente à esta etapa, foi realizado o estudo da cinética do processo de extração supercrítica para obtenção do extrato de folhas da pitanga (Eugenia uniflora) a partir de dados otimizados da literatura; este estudo foi realizado em coluna de extração de 300 mL. Utilizou-se temperatura e pressão de 333,15 K e 60 MPa sob diferentes condições de vazão a fim de estudar o comportamento cinético da extração em relação ao rendimento e à presença de compostos voláteis. Ainda foram realizadas análises para identificação dos compostos por cromatografia em camada delgada (CCD) e cromatografia gasosa acoplada à espectrometria de massas (CG-EM). O estudo do aumento de escala foi realizado usando-se uma unidade piloto equipada com dois extratores de 5 L contendo 3 separadores (S1, S2 e S3); como referência foi empregado o ensaio cinético realizado para folhas de pitanga na coluna de 300 mL. Seguindo o critério de aumento de escala em que se mantém constante a proporção entre a massa de solvente e a massa de matéria-prima, o aumento de escala foi de 17 vezes. Para os experimentos foram selecionadas as seguintes condições de operação para os três separadores S1, S2 e S3: 10 MPa/333,15 K; 7 MPa/303,15 K e 3 MPa /313,15 K, respectivamente. Quatro pontos selecionados da cinética de extração em coluna de 300 Ml foram então reproduzidos. O custo do extrato foi estimado utilizando o simulador SuperPro DesignerÒ obtendo-se um custo do manufatura de US$ 449,89/kg
Abstract: In this work a comparative study of the cost of manufacturing (COM) for different extraction techniques is presented: low pressure solvent extraction (LPSE) in agitation and percolation, and supercritical fluid extraction (SFE). The COM estimation was carried using the processes simulator SuperPro Designer®; agitation and percolation LPSE processes were developed in the simulator. An experimental study to obtain poliphenols by supercritical fluid extraction from leaves of pitanga (Eugenia uniflora) was also performed. For the scale-up study it was assumed that the parameters for the laboratorial scale SFE unit: yield of extraction, time and ratio between the feed mass and solvent mass are kept constant for the equipment in industrial scale. The estimations were carried using literature information for the vegetable matrix macela (Achyrocline satureioides). The studies were done for extraction vessels of 50 L, 100 L and 300 L. The COM for LPSE agitation and percolation processes were: US$ 877.21/kg; US$ 698.73/kg; US$ 573.34/kg and US$ 814.46/kg; US$ 567.86/kg; US$ 384.00/kg, respectively for extractors of 50 L, 100 L and 300 L. It was observed the influence of time and yield parameters on the COM. Later, a study of SFE process COM for the same vegetable matrix was done. For SFE the COM was estimated using the tCER parameter as cycle time, where approximately 70% of extraction bed is exhausted, being this a good estimation. The COM of extract obtained by SFE was US$ 585.49/kg. A comparative evaluation between the tree processes was carried out, and among the major costs factors: investment, raw material and utilities, it was observed that the investment cost is not predominant in the COM of the extracts. The raw material cost certain vessel sizes represented the major cost factor. After this step, a study of the SFE kinetics for leaves of pitanga (Eugenia uniflora) was carried out. The operating conditions were selected from optimized data from literature; this study was done in a 300 mL column vessel. It was utilized temperatures and pressure of 333.15 K and 60 MPa under different flow rates in order to study the kinetic behavior of the overall extraction curve and the presence of volatile compounds. Thin layer chromatography (TLC) and gas chromatography-mass spectrometry (GC-MS) analyses were used for identification of the compounds present in the extract. The scale-up study was carried out using a pilot unit equipped with two extractor of 5L vessel containing 3 separators vessels (S1, S2 and S3); as reference the kinetic assay for pitanga leaves in 300 mL column vessel was used. According to the scaleup criterion that the ratio between solvent mass and raw material mass is kept constant, the scale-up was of 17 times. For the experiment the following operation condition for the three separators S1, S2 and S3 were selected: 10 MPa/333.15 K; 7 MPa/303.15 K and 3 MPa /313.15 K, respectively. Four points selected from kinetic experiment in 300 mL column vessel were reproduced. The extract COM was estimated using simulator SuperPro DesignerÒ (US$ 449,89/kg)
Mestrado
Mestre em Engenharia de Alimentos
10
Pacetta, Cosmo Fernando. "Estudo de diferentes metodologias para a obtenção de extratos de folhas de oliveira (Olea europaea) contendo oleuropeína". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-05052014-135759/.
Streszczenie:
A oleuropeína é o mais abundante biofenol presente nas folhas de oliveira (Olea Europaea), com importantes funções antimicrobiana e antioxidante. Estudos visando à obtenção deste composto têm sido conduzidos, porém, muitos deles utilizam solventes tóxicos e métodos caros. A presente dissertação teve por objetivo estudar diferentes metodologias para a obtenção de extratos de folhas de oliva contendo quantidades significativas de oleuropeína. Os extratos foram obtidos a partir de folhas de oliva micronizadas, com ou sem pré-tratamento para redução do teor de clorofila, submetidas a contatos simples ou múltiplos com diferentes solventes, como dietil éter, clorofórmio, acetona, etanol, 1-propanol, 2-propanol, água e soluções hidroalcoólicas com diferentes concentrações. O contato das folhas micronizadas com os solventes foi promovido pelos seguintes métodos: agitação manual em temperatura ambiente, agitação mecânica a 50 ºC, ultrassom ou uma combinação desses dois últimos, totalizando 38 experimentos, sendo que em 17 destes os extratos foram produzidos na forma líquida e 21 na forma sólida. Os resultados mostraram que, de maneira geral, a etapa prévia de redução do teor da clorofila (realizada através de sucessivos contatos com hexano, diclorometano ou ainda, com CO2 supercrítico) não foi vantajosa, devido à elevada quantidade de solventes utilizados em relação às quantidades de extratos obtidos. Nestes experimentos, a maior concentração de oleuropeína, 1,88%, foi detectada no procedimento em que as folhas micronizadas foram previamente umedecidas com etanol e limpas com CO2 supercrítico, e posteriormente colocadas em contato com a mistura etanol e água, na proporção 1:1, utilizando o ultrassom combinado com a agitação mecânica como método de extração. Nos experimentos finais do trabalho, foi estudada ainda a adição de ácidos orgânicos (cítrico ou acético), juntamente com os solventes hidroalcoólicos (diferentes teores de água) no momento da extração da oleuropeína em banho de ultrassom, utilizando amostras que não foram previamente tratadas para remoção da clorofila. A combinação do ácido acético com a solução etanólica contendo 30 % de água resultou em um extrato com 2,17 % de oleuropeína, em apenas 1 contato com o solvente. Quando três contatos foram utilizados, nestas mesmas condições, o teor de oleuropeína aumentou para 4,8 %, maior do que alguns valores encontrados na literatura, utilizando o mesmo método de extração, indicando que processo ainda pode ser otimizado, utilizando técnicas simples e solventes que não agridam o meio ambiente.Oleuropein is the most abundant biofenol present in olive leaves (Olea europaea), presenting important antioxidant and antimicrobial functions. Studies focusing on obtaining this compound have been conducted; however, many of them use toxic solvents and expensive methods. The present work aimed to study different methodologies for obtaining extracts from olive leaves containing significant amounts of oleuropein. The extracts were obtained from micronized olive leaves, with or without pretreatment for reducing the chlorophyll content, submitted to single and multiple contacts with different solvents such as diethyl ether, chloroform, acetone, ethanol, 1- propanol, 2 -propanol, water and hydroalcoholic solutions at different concentrations. The contact between the micronized leaves and the solvents was promoted by the following methods: manual shaking at room temperature, mechanical agitation at 50 °C, ultrasound or a combination of these last two methods, totaling 38 experiments, from which in 17 of them the extracts were produced in the liquid form, and in 21 in the solid form (as a powder). The results show that, in general, previous step of reducing the content of chlorophyll (performed by successive contacts with hexane, dichloromethane or with supercritical CO2) was not advantageous due to the high amount of solvent used in relation to amounts of extracts. In these experiments, the highest concentration of oleuropein, 1.88 % was detected in the procedure in which the micronized leaves were previously soaked with ethanol and cleaned with supercritical CO2 and then placed in contact with the mixture of ethanol and water in the proportion 1:1, using ultrasound combined with mechanical agitation as extraction method. In the last experiments of the work, the addition of organic acids (citric or acetic acid) together with hydroalcoholic solvents (different water contents) in the extraction of oleuropein in ultrasound was studied, using samples that have not previously been treated for removal of chlorophyll. The combination of acetic acid to the ethanolic solution containing 30 % of water resulted in an extract with 2.17 % of oleuropein, with only one contact to the solvent. When three contacts were used, under the same conditions, the oleuropein content increased to 4.8 %, larger than some values found in the literature, using the same extraction method, indicating that the process can be further optimized using simple techniques and solvents that do not harm the environment.
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Patel, Rushik, i Ajay Kumar. "Dust extractor solution". Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-37979.
Streszczenie:
The following report conducted with the collaboration of the University of Halmstad and HGFrubber company (Halmstad).The focus on the project is eliminating the dust particles from the inner surface of the EPDM basedrubber module.As a part of improving knowledge about the quality and surface finishing and understanding thematerial’s characteristics. This project initiated in February 2018 and end date was set to August2018.The methodology used in this project is based on the Six-Sigma tools which is widely appreciatedglobally to obtain the Zero-defect production.The implementations of this method and other tools are efficient and beneficial to reduce thedefects in the production without compromising the initial quality of the product.This thesis resulted in a quality improvement approach for eliminating the dust using methods suchas Six-Sigma and 5 why’s.
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SOARES, PAULO S. M. "Estudo preliminar do fracionamento de terras raras medias e pesadas em grupos com extracao por solventes". reponame:Repositório Institucional do IPEN, 1994. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10353.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
13
AMÂNCIO, Bárbara Christina Silva. "Bioatividade de extratos de folhas e frutos de Byrsonima spp. (Malphigiaceae) em Lactuca sativa L". Universidade Federal de Alfenas, 2016. https://bdtd.unifal-mg.edu.br:8443/handle/tede/940.
Streszczenie:
O gênero Byrsonima é caracterizado pela alta plasticidade fenotípica e composição florística na América do Sul. B. verbascifolia e B. intermedia, popularmente conhecidas como Murici-cascudo e Murici-pequeno, respectivamente, são espécies conhecidas pela presença rica de taninos, saponinas, catequinas, flavonoides, triterpenos e glicolipídios, que são metabólitos secundários importantes para o desenvolvimento e sobrevivência das plantas e agindo como compostos alelopáticos. A alelopatia é conhecida como interação bioquímica entre vegetais no meio ambiente causando interação planta/planta por meio da competição podendo ser testada por meio de bioensaios utilizando diversos parâmetros. Lactuca sativa L. é uma espécie amplamente utilizada como bioteste, por apresentar grande sensibilidade mesmo quando exposta a baixas concentrações de amostras ambientais e tóxicas. Esta dissertação é apresentada em forma de capítulos de maneira que, o capítulo 1 apresenta uma breve revisão sobre a caracterização botânica de Byrsonima spp., metabólitos secundários de Byrsonima spp., alelopatia e quimioecologia, bioensaios com Lactuca sativa L. para estudos de fitotoxicidade e formas de extração. O capítulo 2 apresenta-se em forma de artigo I e artigo II. No artigo I objetivou-se estudar as propriedades fitotóxicas e citogenotóxicas das folhas e frutos de B. verbascifolia e B. intermedia em L. sativa L. utilizando o método sanduiche. Verificou-se que frutos de B. intermedia são responsáveis pela maior inibição da germinação de alface em relação às folhas dessa espécie. O alongamento de raiz de alface exposta aos órgãos de B. verbascifolia demonstrou efeitos estimulatórios e os órgãos de B. intermedia apresentaram efeitos inibitórios no crescimento das raízes. O índice mitótico evidenciou efeito alelopático de Byrsonima spp. pela redução da divisão celular no meristema radicular de alface, sendo o estímulo no alongamento de raízes provocado por B. verbascifolia compreendido como consequência de expansão celular e não de atividade mitótica. Foi observado efeito aneugênico das espécies de Byrsonima spp. sendo a maior frequência de C-metáfase e stickness em frutos de B. verbascifolia e folhas de B. intermedia. O artigo II apresenta um trabalho cujo objetivo foi averiguar a fitotoxicidade de diferentes extratos foliares de B. verbascifolia e B. intermedia em bioensaio com Lactuca sativa L. Os resultados evidenciaram que os extratos de folhas de B. verbascifolia e B. intermedia, sobretudo o extrato etanólico, possuem potencial fitotóxico e citotóxico. Esses efeitos diferem em função da forma de extração (aquoso frio, quente e etanólico), provavelmente devido à composição dos metabólitos secundários.The Byrsonima genus is characterized by high phenotypic plasticity and composition in South America. B. verbascifolia and B. intermedia, popularly known as Murici-cascudo and Murici-pequeno, respectively, are known species by the rich presence of tannins, saponins, catechins, flavonoids, triterpenes and glycolipids, secondary metabolites that are important for the development and survival of plants, and act as allelopathic compounds. Allelopathy is known as plant biochemical interaction between the environment causing interaction plant/plant through competition can be tested by bioassay using various parameters. Lactuca sativa L. is a species widely used as a bioassay for presenting high sensitivity even when exposed to low concentrations of toxic and environmental samples. This work is presented in the form of chapters so that, Chapter 1 provides a brief review of the botanical characterization Byrsonima spp., secondary metabolites of Byrsonima spp., allelopathy and quimioecology, bioassays with Lactuca sativa L. for phytotoxicity studies and forms of extraction. Chapter 2 presents in the form of paper I and paper II. Paper I aimed to study the phytotoxic properties and cytogenotoxic of leaves and fruits of B. verbascifolia and B. intermedia in L. sativa L. using the sandwich method. It was found that fruits of B. intermedia are responsible for the inhibition of germination of lettuce leaves with regard to this species. The lettuce root elongation organs exposed to B. verbascifolia showed stimulatory effects and organs of B. intermedia showed inhibitory effects on the growth of roots. The mitotic index showed allelopathic effect of Byrsonima spp. the reduction of cell division in root meristem of lettuce, and stimulating the roots stretching caused by B. verbascifolia understood as a consequence of cell expansion and not of mitotic activity. It was observed effect aneugenic of Byrsonima spp. being the highest frequency of C-metaphase and stickness in fruits of B. verbascifolia and leaves of B. intermedia. Paper II presents a work whose purpose was to determine the phytotoxicity of different plant extracts of B. verbascifolia and B. intermedia in bioassay Lactuca sativa L. The results showed that the extracts of leaves of B. verbascifolia and B. intermedia, especially ethanol extract, have phytotoxic and cytotoxic potential. These effects are different depending on the extraction form (aqueous cold, hot and ethanol), probably due to the composition of secondary metabolites.
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
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Hatumura, Pedro Henrique. "Efeito do solvente na separação de metabólitos secundários em extratos de grãos de Coffea arabica". Universidade Estadual de Londrina. Centro de Ciências Exatas. Programa de Pós-Graduação em Química, 2014. http://www.bibliotecadigital.uel.br/document/?code=vtls000190994.
Streszczenie:
O efeito do solvente na separação dos metabólitos em extratos de grãos crus de duas cultivares de cafés, Bourbon e IPR 108 foi investigado em cromatografia de coluna aberta. Com o objetivo de estudar a influência dos parâmetros solvatocrômicos α, β e π foram utilizadas quatro fases móveis de mesma polaridade. Métodos quimiométricos de análise hierárquica (AH) e análise de componentes principais (ACP) foram aplicados aos cromatogramas (CLAE) e espectros (UV-DAD-CLAE). Os resultados mostraram que a maior eficiência no fracionamento foi obtida usando a fase móvel ternária acetona-diclorometano-etanol (32:36:32 v/v/v) na cromatografia de coluna. A análise dos espectros dos cromatogramas UV-DAD-CLAE de ambas cultivares mostraram maior diversidade de perfis de espectros quando o extrato foi eluído com a fase ternária. Deste modo, tanto a análise de cromatogramas quanto a dos espectros mostraram a vantagem de se utilizar fases móveis ternárias. Além disso, ficou evidenciado a separação entra as frações das diferentes fases móveis, indicando que as características do solvente (α, β e π) são importantes na separação dos diferentes metabólitos.The effect of the solvent on the separation of metabolites in extracts of raw coffee beans of two cultivars, Bourbon and IPR 108 was investigated with open column chromatography With the aim of studying the influence of the solvatochromic parameters α, β and π four mobile phases with the same polarity were used. Chemometric methods of hierarchy analysis (HA) and principal component analysis (PCA) were applied to chromatograms (HPLC) and spectra (HPLC-DAD-UV). The results showed that the highest efficiency in fractionation was achieved using the ternary mobile phase acetone-dichloromethane-ethanol (32:36:32 v / v / v) in column chromatography. The spectral analysis of the HPLC-DAD-UV chromatograms of both cultivars showed greater diversity of spectral profiles when the extract was eluted with the ternary phase. Thus, both the analysis of the chromatograms and the spectra showed the advantage to using the ternary mobile phase. Furthermore, the separation between the fractions of different mobile phases was evident, indicating that the characteristics of the solvent (α, β and π) are important in the separation of different metabolites.
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Kitzberger, Cíntia Sorane Good. "Obtenção de extrato de cogumelo shiitake (Lentinula edodes) com CO2 a alta pressão". Florianópolis, SC, 2005. http://repositorio.ufsc.br/handle/123456789/102121.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Alimentos.Made available in DSpace on 2013-07-16T00:05:44Z (GMT). No. of bitstreams: 1 221539.pdf: 3733353 bytes, checksum: d78f37666da067ab14cd76a7615aed9e (MD5)
A extração supercrítica (ESC) é uma tecnologia que vem se destacando dentre as demais extrações por sua seletividade e por empregar baixas temperaturas, produzir um extrato livre de resíduos de solventes, garantindo assim extratos de alta qualidade em compostos de interesse, além da técnica ser considerada segura para o meio ambiente. No processo de ESC a variação das condições de temperatura e pressão de operação permitem relacionar eficiência e condições ótimas de processo. Levando-se em consideração as vantagens que a ESC oferece, o objetivo deste trabalho foi seu emprego na obtenção de extratos do cogumelo shiitake (Lentinula edodes) em diferentes temperaturas e pressões de operação e avaliar rendimento, composição, atividade antioxidante e antimicrobiana, além de comparar os resultados obtidos com a ESC CO2 utilizando co-solventes e com a extração líquido-líquido (ELL). Lentinula edodes (Berk.) Pegler é o segundo cogumelo mais largamente cultivado no mundo. É considerado boa fonte de nutrientes como proteínas, carboidratos, lipídeos, minerais e vitaminas. Dentre suas propriedades terapêuticas destacam-se a ação antitumoral, a ação hipocololesterolêmica, as atividades antifúngica e antimicrobiana, a redução do colesterol e a ação antioxidante. As condições de operação na ESC foram temperaturas de 30 a 50°C e pressões de 150 a 350 bar que forneceram rendimentos de 0,53 a 1,01%. Foram usados os co-solventes diclorometano, acetato de etila e etanol. A ELL empregou os seguintes solventes n-hexano, diclorometano, acetato de etila e água. Para a quantificação e identificação dos extratos da ESC e ELL foram realizadas, análises cromatográficas através da cromatografia gasosa e cromatografia gasosa acoplada à espectrometria de massas, sendo os principais componentes do shiitake os ácidos graxos como palmítico, linoléico e o ergosterol (pró-vitamina D). Os extratos da ELL e ESC com co-solvente apresentaram atividade antioxidante, com valores de EC50 na faixa de 132,11 a 190,30 mg/mL. Para as análises antimicrobianas os extratos foram mais efetivos contra as bactérias M. luteus e B. cereus. Os valores de MIC ficaram em torno de 0,5 mg/mL para os extratos obtidos a 50°C e 150 bar e 30°C e 200 bar contra M. luteus e de 0,25 mg/mL para o extrato 30°C e 300 bar contra B. cereus. Os modelos de SOVOVÁ (1994) e de Martinez (2003), que foram utilizados para descrever a curva de extração representaram adequadamente os dados experimentais para a ESC de cogumelo shiitake.
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FAVARO, DEBORA I. T. "Estudo do comportamento de alguns lantanidios nas extracoes com misturas binarias de acido DI-(2-ETILHEXIL) fosforico (HDEHP) tenoiltrifluoroacetona". reponame:Repositório Institucional do IPEN, 1985. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9843.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Kamatou, GPP, Zyl RL Van, Vuuren SF Van, AC Figueiredo, JG Barroso, LG Pedro i AM Viljoen. "Seasonal variation in essential oil composition, oil toxicity and the biological activity of solvent extracts of three South African Salvia species". Elsevier, 2007. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000526.
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Aromatic plants contain both volatile and non-volatile fractions and the chemical composition of these two fractions may be influenced by seasonal
changes. The essential oil and solvent extracts of S. africana-caerulea, S. africana-lutea and S. lanceolata, collected at the same locality throughout the 2005 growing season, were compared in terms of essential oil composition, yields and biological activities. Mostly quantitative, rather than qualitative variationwas observed in the oil composition of each species.Major fluctuations in the composition of S. africana-caerulea oil included limonene (2–33%) and viridiflorol (2–24%). Levels of α-pinene (1–12%), myrcene (2–12%) and α-eusdesmol (trace-13%) fluctuated seasonally in the S. africana-lutea oil.
In S. lanceolata, considerable changeswere noted for β-caryophyllene (1–19%), β-caryophyllene oxide (1–21%) and ledol (3–12%). The extract prepared
from S. lanceolata harvested inwinterwas more active against Gram-positive bacteria. The S. africana-caerulea extract exhibited the most favourable antiplasmodial activity when harvested in winter (IC50 value: 12 μgml−1), which contrasts with the lowest anti-plasmodial activity of S. lanceolata obtained at
the same period (IC50 value: 43 μgml−1). The anti-oxidant activity of the solvent extracts also displayed variation over seasons with thewinter collection of
S. africana-lutea yielding the most favourable anti-oxidant activity (IC50 value: 10 μg ml−1). All the solvent extracts prepared from the winter collection exhibited the lowest toxicity (20bIC50 valuesb60 μg ml−1), while the three essential oils obtained from autumn collection were more toxic (0.03bIC50 valuesb0.4 μg ml−1).
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Tófoli, Rodolfo José. "Avaliação de biocompostos e composição mineral de extratos provenientes de duas macroalgas lóticas do estado de São Paulo /". Assis, 2017. http://hdl.handle.net/11449/150494.
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Orientador: Ivanise Guilherme BrancoBanca: Eliana Janet Sanjinez Argandoña
Banca: Cássia Roberta Malacrida Mayer
Resumo: No Brasil, há uma grande biodiversidade de espécies de algas lóticas, Dentre as mais conhecida, encontradas em rios e riachos da região sudeste do estado de São Paulo destaca-se a Oedogonium sp. e a Nitella microcarpa var. wrightii., dois gêneros de algas verdes. Entretanto, estudos de caracterização química de extratos destas algas ainda são inexistentes. Por esse motivo destaca-se a importância deste trabalho, o qual encontra-se subdivido em dois estudos. O primeiro teve por objetivo avaliar e quantificar compostos fenólicos e capacidade antioxidade de extratos de diferentes solventes da alga Oedogonium sp. Utilizou-se um delineamento experimental de mistura para determinar a influência dos solventes e verificou-se qual desses apresentou melhor rendimento na extração desses compostos da alga em pó. O segundo estudo teve por objetivo realizar a caracterização de duas macroalgas verdes: Nitella microcarpa var. wrightii, e Oedogonium sp., através da obtenção de um extrato, com o melhor sistema de solventes obtidos no primeiro estudo. Desta forma, foi possível quantificar quanto a presença de minerais, flavonoides, umidade, carotenoides, compostos fenólicos e capacidade antioxidante. No primeiro estudo, os resultados sugeriram que a mistura acetona-etanol apresentou melhor rendimento de extração tanto para compostos fenólicos como à capacidade antioxidante. No segundo estudo, a alga Oedogonium sp. destacou-se por apresentar uma grande quantidade de carotenoides totais. Já a e... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In Brazil, there is a great biodiversity of lotic algae species. Among the most well known species found in rivers and streams in the southeast region of the state of São Paulo is Oedogonium sp. and Nitella microcarpa var. Wrightii., Two genus of green algae. However, studies of chemical characterization of extracts of these algae are still non existent. For this reason the importance of this work is highlighted, which is subdivided in two studies. The first one had the objective to evaluate and quantify phenolic compounds and antioxidant capacity of extracts of different solvents of the algae Oedogonium sp. An experimental design of the mixture was used to determine the influence of the solvents and it was verified which of them presented better yield in the extraction of these compounds from the powdered seaweed. The second study aimed to characterize two green macroalgae: Nitella microcarpa var. Wrightii, and Oedogonium sp., by obtaining an extract, with the best solvent system obtained in the first study. In this way, it was possible to quantify the presence of minerals, flavonoids, moisture, carotenoids, phenolic compounds and antioxidant capacity. In the first study, the results suggested that the acetone-ethanol-water mixture had a better extraction yield for both phenolic compounds and antioxidant capacity. In the second study, the alga Oedogonium sp. was characterized by a large amount of total carotenoids. The other alga, of the species Nitella microcarpa var... (Complete abstract click electronic access below)
Mestre
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Rodrigues, Vítor Hugo dos Louros. "Produção de extratos bioativos a partir de resíduos da CMC-Biomassa S.A. por extração supercrítica com solventes verdes". Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22518.
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Mestrado em Engenharia QuímicaEsta dissertação teve como objetivo estudar a extração e caraterização de compostos bioativos com valor acrescentado, nomeadamente os ácidos triterpénicos (TTAs) (ácidos betulínico, betulónico, oleanólico, ursólico e derivados acetilados dos dois últimos) da folhagem de Eucalyptus globulus. Efectuaram-se extracções com metanol, etanol e diclorometano, pelo método Soxhlet, e com dióxido de carbono na extração supercrítica (SFE), modificado ou não com etanol (cossolvente). Analisaram-se os extractos por FTIR-ATR, GC-MS e SEM, em conjunto com métodos hierárquicos de análise de agrupamentos (clusters) com vista à comparação dos diferentes extractos entre si, com a biomassa original e com os TTAs puros. Verificou-se que as folhas de eucalipto contêm uma quantidade elevada de extractáveis, com rendimentos totais de 30.34 % (m/m) para extrações Soxhlet com metanol, e 7.32 % com diclorometano. Por SFE os rendimentos totais variaram entre 1.52 e 3.16 % para extracções realizadas com CO2 a 200 bar com 0 e 5.0 % (m/m) de etanol, respectivamente. Após optimização alcançaram-se rendimentos totais de 3.95 % e de TTAs de 0.67 % (m/m), para extracções a 250 bar com CO2 contendo 5.0 wt.% etanol, a 40 ᵒC e caudal de 12 gCO2 min-1. A remoção específica de ceras das folhas foi estudada com êxito obtendo-se posteriormente extratos particularmente ricos em TTAs. Realizou-se um estudo cinético para as condições ótimas de SFE, usando biomassa tal e qual (estilhas sem pré-tratamento) ou pré-tratada para redução de granulometria (moagem) ou remoção de ceras. Destes resultados destaca-se o elevado rendimento total obtido com a amostra moída (5.90 %, ao fim de 6 h) e o bom desempenho da biomassa sem tratamento em termos de extração de TTAs (rendimento 0.64 % e concentração de 16.5 %). A biomassa com pré-remoção das ceras gerou extratos com concentrações de TTAs similares aos da biomassa não tratada. No geral, o presente trabalho fornece informação útil para o estudo da extração de compostos bioativos da folhagem de E. globulus, assim como detalhes de composição e rendimentos que podem constituir o ponto de partida para estudos ainda mais detalhados a realizar futuramente.
This work focuses the extraction and characterization of high added value bioactive compounds obtained from Eucalyptus globulus leaves, namely triterpenic acids (TTAs) such as betulonic, betulinic, oleanolic and ursolic acids, and the acetylated derivates of the last two. The extractions were done using methanol, ethanol, and dichloromethane for the Soxhlet method, and carbon dioxide for the supercritical fluid extraction (SFE), modified or not with ethanol (cosolvent). The extracts were characterized by FTIR-ATR, GC-MS and SEM, together with the hierarchical cluster analysis method for comparison of the different extracts between themselves and with the original biomass and with the pure TTAs. The results revealed Eucalyptus leaves have high content of extractives, namely 30.34 wt.% for Soxhlet extraction with methanol and 7.32 wt.% with dichloromethane. With SFE the total extraction yield varied between 1.52 and 3.16 wt.%, for extractions at 200 bar with CO2 containing 0 wt.% and 5.0 wt.% of ethanol, respectively. After optimization, total extraction yields of 3.95 wt.% and 0.67 wt.% for TTAs were attained, at 250 bar with CO2 containing 5.0 wt.% ethanol, temperature of 40 ᵒC and flow rate of 12 gCO2 min-1 The removal of waxes from the leaves was successfully studied enabling the production of extracts rich in TTAs. Kinetic studies were performed at the SFE optimized conditions to compare the effect of crushing or dewaxing the leaves in relation to untreated leaves. Highest yields were obtained with the crushed leaves (5.90 wt.%, after 6 h) while in terms of TTAs extraction the best results were obtained with untreated biomass (yield 0.64 wt.%, and concentration 16.5 wt.%). The extracts obtained with untreated and dewaxed biomass samples presented similar concentrations of TTAs. The present work presents useful information for the extraction of bioactive compounds from E. globulus leaves as well as attainable yields and composition that may guide future comprehensive studies.
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Ascari, Jociani. "ESTUDO QUÍMICO E BIOATIVIDADES DE Baccharis uncinella DC". UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2007. http://tede2.uepg.br/jspui/handle/prefix/2120.
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Previous issue date: 2007-02-28Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Baccharis uncinella (Asteraceae), popularly known as vassoura, is little known from the chemical point of view, with only two earlier scientific works on their secondary metabolites - the volatile constituents. In the present study, the essential oil from the leaves of B. uncinella and nine extracts obtained in a Soxhlet apparatus with organic solvents starting from the leaves, barks and log were analyzed by CCD, UV and IV and submitted to activity tests against microorganisms; besides, the interactions between the aqueous extract of the leaves with human erytrocytary cells of the sanguine types O+, O-, A+ and B+ were also analyzed. In the antimicrobial tests, the microfungus Candida albicans, as well as the Gram-positive Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus and S. saprophyticus and the Gram-negative bacteria Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa were used. The essential oil showed action against B. cereus, S. aureus and C. albicans, in the same way as all of the organic extracts, but the growth of S. saprophyticus was not inhibited by no one of the extracts. The extracts of the barks, when compared with those obtained from other parts of the plant, were active against the largest number of microorganisms and presented the more strong activities. The minimum inhibitory concentration of the essential oil was estimated as 100/mL against S. aureus as well as against C. albicans, wich could be considered a moderate antimicrobial activity. We have isolated small amounts of the three major phenolic components found in the leaves, and the analysis of their UV- and IR-spectra showed the structural features of hydroxylaryl-propenoic acids for these compounds that were found for the first time in this plant species. The analyses of GC-MS of the essential oil produced by hydrodistillation of the leaves collected at the Paraná State presented low monoterpene content (2.29%) and the following sesquiterpenes as the main components: spathulenol 17.20%, caryophyllene oxide 16.20%, transcaryophyllene 10.48%, eudesmol 7.55%, germacrene D 6.28% and cadinol 5.18%. Another oil sample was obtained using the same conditions, but starting with leaves collected in the highland area of Santa Catarina, also presented spathulenol as the main component (15.83%), but it contained 36% in monoterpenes, a very similar composition to those published for samples from the State of Rio Grande do Sul. The interactions among the aqueous extract of the leaves with human erytrocytes isolated from the sanguine types O+, O-, A+ and B+, being verified that the extract presents a non-lytic activity in the analyzed concentrations of 22, 110 and 220/mL. This non-hemolytic profile was observed as similar for all tested blood types. The serological types A+ and O- presented a similar pattern of free Hb oxidation in solution, and the same profile was observed in the new suspension of the precipitate. In the analysis of MEV we observed the qualitative aspects regarding the interaction of the aqueous extract with the architecture of the erythrocyte. In the assays of DPPH with low concentrations, 1.5 x 10-4 and 7.8 x 10-5 mg/mL, it was possible to quantify a partial reduction in the free radicals concentration of 20.10% and 9.25% respectively.
Baccharis uncinella (Asteraceae), popularmente conhecida como vassoura, é pouco conhecida do ponto de vista químico, havendo apenas dois trabalhos científicos anteriores sobre seus metabólitos secundários - os constituintes voláteis. No presente estudo, o óleo essencial das folhas de B.uncinella e nove extratos obtidos em Soxhlet com solventes orgânicos a partir das folhas, cascas e lenho foram analisados por CCD, UV e IV e submetidos a testes de atividade contra microrganismos; além disto, foram também analisadas as interações de extrato aquoso das folhas com células eritrocitárias humanas dos tipos sangüíneos O+, O-, A+ e B+. Nos testes antimicrobianos, foram usados o microfungo Candida albicans, as bactérias Gram-positivas Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus e S. saprophyticus e as bactérias Gram-negativas Escherichia coli, Klebsiella pneumoniae e Pseudomonas aeruginosa. O óleo essencial apresentou ação contra B. cereus, S. aureus e C. albicans, da mesma forma que todos os extratos orgânicos, mas o crescimento de S. saprophyticus não foi inibido por nenhum deles. Os extratos das cascas, quando comparados com os obtidos de outras partes da planta, foram ativos contra o maior número de microrganismos e apresentaram as mais fortes atividades. A concentração inibitória mínima do óleo essencial foi determinada como 50L/mL tanto contra S. aureus como contra C. albicans, podendo ser considerada uma atividade antimicrobiana moderada. Foram isoladas pequenas quantidades dos três compostos fenólicos majoritários, cujas análises indicam trata-se de derivados de ácidos hidroxiarilpropenóicos, encontrados pela primeira vez nesta espécie vegetal. As análises de CG-EM do óleo essencial produzido por hidrodestilação a partir de folhas coletadas no segundo planalto do Paraná, apresentaram baixo teor de monoterpenos (2,29%) e os seguintes sesquiterpenos como principais componentes: espatulenol 17,20%, cariofileno óxido 16,20%, trans-cariofileno 10,48%, eudesmol 7,55%, germacreno D 6,28% e cadinol 5,18%. Outra amostra de óleo obtida nas mesmas condições, mas a partir de folhas coletadas na região serrana de Santa Catarina, também apresentou espatulenol como principal componente (15,83%), mas quase 36% em monoterpenos, uma composição muito similar às publicadas sobre amostras da Serra Gaúcha. Foram analisadas as interações entre extrato aquoso das folhas com células eritrocitárias humanas dos tipos sangüíneos O+, O-, A+ e B+, sendo que o extrato apresenta uma atividade não-lítica nas concentrações analisadas de 22, 110 e 220 /mL, similar para todas tipagens analisadas. Os sorotipos A+ e O- testados apresentaram um padrão similar de oxidação da Hb livre em solução e, o mesmo perfil foi observado na ressuspensão dos precipitados. Na análise de MEV foram verificados aspectos qualitativos a respeito da interação do extrato aquoso com a arquitetura da célula eritrocitária. Baixas concentrações do extrato, 1,5 x 10-4 e 7,8 x 10-5 mg/mL, apresentaram atividade redutora em presença de DPPH, de 20,10% e 9,25% respectivamente.
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Vazhacharickal, Prem Jose [Verfasser], i Jeena [Verfasser] Joseph. "Antimicrobial property and effects of various solvent extracts of Arrowroot (Curcuma angustifolia) powder against E.coli and Staphylococus aureus under varying concentrations / Prem Jose Vazhacharickal ; Jeena Joseph". Göttingen : Cuvillier Verlag, 2016. http://d-nb.info/1102186139/34.
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Cardenas, Toro Fiorella Patricia 1980. "Obtenção de extratos enriquecidos em carotenoides e produtos hidrolisados através do fracionamento da fibra de palma prensada com solventes limpos e fluidos pressurizados". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254910.
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Orientadores: Maria Angela de Almeida Meireles Petenate, Tânia Forster CarneiroTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: A fibra de palma prensada (Elaes guineensis) é um resíduo procedente da indústria de extração de óleo de palma que possui na sua composição compostos bioativos tais como alfa- e beta-caroteno, assim como os polissacarídeos (celulose e hemicelulose). Estes compostos podem ser recuperados mediante processos de extração e hidrólise com a finalidade de produzir de forma sustentável, extratos enriquecidos com carotenoides e produtos hidrolisados com aplicação na indústria química, de alimentos e farmacêutica. Entre as tecnologias que utilizam solventes limpos a altas e baixas pressões, temos a extração por Soxhlet (LPSE-SOX), extração por percolação (LPSE-PE), extração por líquido pressurizado (PLE), extração com fluído supercrítico (SFE) e hidrólise subcrítica com água (SubWH). Neste trabalho, um processo integrado utilizando SFE e SubWH foi proposto como modelo de aproveitamento integral da fibra de palma prensada. O estudo incluiu a avaliação dos efeitos dos parâmetros operacionais de extração: temperatura e pressão empregando uma razão mássica de solvente por massa de matéria-prima (S/F) de 30 na obtenção de um extrato rico em carotenoides; e dos parâmetros operacionais de hidrólise: temperatura, pressão, S/F e tempo de residência na produção de monossacarídeos e oligossacarídeos nos produtos hidrolisados. Após esse primeiro estudo, um segundo estudo dos processos de extração LPSE-SOX, LPSE-PE e PLE utilizando etanol como solvente limpo foi realizado com o objetivo de explorar as condições de operação: temperatura, pressão e vazão na razão S/F de 20, que favorecessem a produção de um extrato rico em carotenoides (alfa e beta-caroteno) incluindo a avaliação econômica de cada processo. Os resultados do primeiro estudo para o SFE utilizando dióxido de carbono como solvente indicaram que o maior rendimento de carotenoides totais no extrato foi 800 ± 200 ug beta-caroteno/g extrato na condição de 318 K (45°C) e 15 MPa. Posteriormente, os experimentos de hidrólise subcrítica da fibra de palma desengordurada obtiveram uma mistura de produtos hidrolisados e produtos de degradação de açúcares, sendo a condição de 523 K (250°C), 15 MPa, tempo de residência de 2,5 min e S/F de 120 aquela com maiores rendimentos de açúcares redutores totais (22,9 g glicose/100 g carboidrato). Este estudo mostrou a viabilidade de integração de processos para o melhor aproveitamento da fibra de palma prensada. Na segunda parte do estudo, os processos de extração com etanol à baixa e alta pressão com melhores rendimentos de carotenoides foram: 305 ± 18 ug alfa-caroteno/g extrato e 713 ± 46 ug beta-caroteno/g extrato para o processo PLE na condição de 308 K (35°C), 4 MPa, 2,4 g/min e 37 min; 142 ± 13 ug alfa-caroteno/g extrato e 317 ± 46 ug beta-caroteno/g extrato para o processo LPSE-SOX num tempo de 6 h; 79 ± 9 ug alfa-caroteno/g extrato e 195 ± 20 ug beta-caroteno/g extrato para o processo LPSE-PE na condição de 308 K (35°C), 2,4 g/min e 37 min. Os custos de manufatura (COM) na escala industrial de 0,5 m3 utilizando 2 extratores em modo contínuo foram de US$98,1/g carotenoide para o processo LPSE-SOX; US$48,9/g carotenoide para o processo LPSE-PE e US$28,7/g carotenoide para o processo PLE. Diante dos resultados obtidos no primeiro e segundo estudo, um estudo cinético dos processos de extração a altas pressões PLE e SFE foi realizado nas condições operacionais que obtiveram altos rendimentos de carotenoides no extrato. O rendimento de extração na razão S/F de 7 e 10 resultou em 90% do total do extrato obtido no final da extração para o processo PLE e SFE, respectivamente. Para o processo PLE e SFE os menores valores de COM foram encontrados para as capacidades de extratores industriais de 0,05 m3 e 0,5 m3. Para o processo PLE, na razão S/F de 8 obtiveram-se os menores valores de COM e COM* específico: US$30,4/kg extrato e US$0,02/g carotenoide para 0,5 m3. Uma tendência similar foi observada para o processo SFE com valores de COM de US$30,8/kg extrato e US$0.08/g carotenoide para 0,5 m3. Baseados nestes resultados, o processo PLE apresenta uma melhor vantagem econômica que o processo SFE e pode ser considerado como a primeira etapa do processo integrado de obtenção de extrato rico em carotenoides seguido do processo SubWH para a obtenção de produtos hidrolisados
Abstract: Pressed palm fiber (Elaes guineensis) is a residue obtained from the palm oil extraction industry that is a source of bioactive compounds such as alpha- and beta-carotene present in the residual oil and polysaccharides (cellulose and hemicellulose), which can be recovered by extraction and hydrolysis processes in order to produce in a sustainable manner extracts enriched with carotenoid for direct application in food industry as additives and/or formation of hydrolysate products with high yields of monosaccharides and oligosaccharides with application in the chemical food and pharmaceutical industry. Technologies that use clean solvents at high and low pressures include Soxhlet extraction (LPSE-SOX), extraction by percolation (LPSE-PE), pressurized liquid extraction (PLE), supercritical fluid extraction (SFE) and subcritical hydrolysis (SubWH). In this work, an integrated process using SFE and SubWH was proposed as the model of completely utilization of pressed palm fiber. The study included the evaluation of the effects of operating parameters of extraction: temperature and pressure at the ratio of solvent mass to feed mass (S/F) of 30 in the obtaining of extracts rich in carotenoids and the study of operational parameters of hydrolysis: temperature, pressure, S/F and residence time on the production of monosaccharides and oligosaccharides in the hydrolyzed products. After this first study, a second study of the extraction processes LPSE-SOX, LPSE-PE and PLE using ethanol as a clean solvent was conducted in order to explore the operational conditions: temperature, pressure and flow rate at S/F ratio of 20, which promotes the production of an extract rich in carotenoids (alpha- and beta-carotene) including the economic evaluation of each process. Results of the first study for SFE using carbon dioxide as a solvent indicated that the highest yield of total carotenoids in the extract was 800 ± 200 ug alpha-carotene/g extract at the condition of 318 K (45°C) and 15 MPa. Thereafter, the experiments of subcritical hydrolysis of defatted pressed palm fiber resulted in a mixture of hydrolysate products and sugar degradation products, where the condition of 523 K (250°C), 15 MPa, residence time of 2.5 min and S/F 120 presented the highest yield of total reducing sugars (glucose 22.9 g/100 g carbohydrate). In the second part of this study, the extraction processes with ethanol at low and high pressure with highest yields of carotenoids in extracts were: 305 ± 18 ug alpha-carotene/g extract and 713 ± 46 ug beta-carotene/g extract for the PLE process at the condition of 308 K (35°C), 4 MPa, 2.4 g/min and 37 min; 142 ± 13 ug alpha-carotene/g extract and 317 ± 46 ug beta-carotene/g extract for LPSE-SOX process at 6 h; and 79 ± 9 ug alpha-carotene/g extract and 195 ± 20 ug beta-carotene/g extract for LPSE-PE process at condition of 308 K (35°C), 2.4 g/min and 37 min. The cost of manufacturing (COM) for the industrial scale of 2 extractors in continuous mode with capacity of 0.5 m3 were US$98.1/g carotenoid for the LPSE-SOX process, US$48.9/g carotenoid for the LPSE-PE process and US$28.7/g carotenoid for the PLE process. From the results obtained in the first and second study, a kinetic study of the PLE and SFE processes at the operating conditions which obtained the highest carotenoid yields from pressed palm fiber was carried out in order to find the adequate processing time and manufacturing cost. The results showed that the extraction at the S/F ratio of 7 and 10 resulted in extract yields higher than 90% for the PLE and SFE process. On the other hand, the carotenoid yield of carotenoids in the extract increased with the S/F ratio. For PLE and SFE processes, the lowest COM values were found for the industrial scale of extractors of 0.05 and 0.5 m3. For PLE process, the S/F ratio of 8 resulted in the lowest COM and specific COM* value: US$30.4/kg extract and US$0.02/g carotenoid for 0.5 m3. A similar trend was observed for the SFE process with values of US$30.8/kg extract and US$0.08/g carotenoid for capacity of 0.5 m3. Based on these results, the PLE process is economically more advantageous than the SFE process and PLE can be considered as the first step of the integrated process for obtaining of extract rich in carotenoids followed by SubWH for obtaining of hydrolysate products
Doutorado
Engenharia de Alimentos
Doutora em Engenharia de Alimentos
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Andrade, Kátia Suzana. "Avaliação das técnicas de extração e do potencial antioxidante dos extratos obtidos a partir de casca e de borra de café (Coffea arabica L.)". reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/95258.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia de Alimentos, Florianópolis, 2011Made available in DSpace on 2012-10-25T23:17:31Z (GMT). No. of bitstreams: 1 296786.pdf: 1619266 bytes, checksum: 4c4959b572f948a62f2ff59a3e260ce3 (MD5)
O Brasil é atualmente o maior produtor mundial de café, representando 30% do mercado, com um volume equivalente a soma dos outros seis países de maior produção. A grande produção e também o consumo de café levam a geração de uma enorme quantidade de resíduos. Devido à importância dos diferentes compostos presentes nos resíduos de café, a obtenção de extratos a partir dessas fontes seria uma alternativa de agregação de valor de valor a um subproduto agroindustrial tão abundante. Assim, o objetivo deste estudo foi a obtenção de extratos de casca e de borra de café, utilizando tecnologia supercrítica e métodos de extração a baixa pressão, a fim de avaliar o potencial antioxidante e a composição dos extratos, e ainda fazer a determinação dos parâmetros cinéticos do processo de ESC. Os extratos obtidos pelos métodos a baixa pressão (soxhlet e ultrassom) mostraram maiores rendimentos quando comparados à extração supercrítica. O potencial antioxidante foi avaliado pelos métodos DPPH, ABTS e Folin-Ciocalteau, sendo que os melhores potenciais antioxidantes foram verificados para os extratos de casca de café obtidos à baixa pressão. A quantificação e identificação dos extratos foram avaliadas por Cromatografia Líquida de Alta Eficiência (CLAE). Os principais compostos identificados foram cafeína e ácido clorogênico.
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Mendoza, Garnica Karina. "EFECTO DEL TIPO DE SOLVENTE SOBRE LA CONCENTRACIÓN DE COMPUESTOS BIOACTIVOS, SAPONINAS Y CARACTERÍSTICAS FÍSICAS DE EXTRACTOS DE HOJAS DE GUAYABA (Psidium guajava L.) Y AGUACATE (Persea americana Mill)". Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2019. http://hdl.handle.net/20.500.11799/99169.
Streszczenie:
Tesis de LicenciaturaLa producción de residuos agroindustriales en México comprende más de 50 millones de t de hojas y tallos, que se ha demostrado que son fuente de diversos compuestos bioactivos. Igualmente, es el cuarto productor de guayaba (Psidium guajava L.) y aporta 3 de cada 10 t del aguacate (Persea americana Mill) producido mundialmente. Estos frutales tienen propiedades antimicrobianas, bactericidas, cicatrizantes, entre otras. Por lo tanto el objetivo del presente trabajo fue evaluar el efecto de tres solventes metanol, etanol y agua (metanol 100%, etanol 100%, agua 100%, etanol/metanol 50:50, metanol/agua 50:50 y etanol/agua 50:50 V/V) sobre la concentración de fenoles totales obtenido por Método de Folin- Ciocalteu, fenoles totales por medio de Método de Salem et al. (2011), concentración de saponinas, pH y color (L*, a*, b*, c* y h) en extractos de hojas de guayaba (Psidium guajava L.) y aguacate (Persea americana Mill). El mayor contenido de fenoles totales fue mediante el método de Folin-Ciocalteu en hojas de guayaba con Metanol/Agua (76.4 mg GAE g-1), aunque este solvente no es apto para alimentos. Por el método de Salem et al. (2011), la mayor concentración fue en extractos de hojas de aguacate con metanol 100% (190.267 mg g-1). La mayor concentración de saponinas se encontró con Metanol/Agua en hojas de aguacate (154.03 mg g-1). El pH más bajo se encontró en extractos acuosos y en las otras combinaciones se observó cercano a la neutralidad. Finalmente, la determinación de color por medio del círculo cromático de CIELAB, indicó que los valores a pesar de ser positivos, fueron bajos por lo cual, fueron tonos obscuros de rojos a verdes
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Braga, Mara Elga Medeiros. "Extração supercritica de curcuminoides de Curcuma longa L. usando como solvente mistura de CO2 + etanol e/ou isopropanol : um estudo da cinetica e das propriedades funcionais do extrato". [s.n.], 2002. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254881.
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Orientador : Maria Angela de Almeida MeirelesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-01T00:53:19Z (GMT). No. of bitstreams: 1 Braga_MaraElgaMedeiros_M.pdf: 31955509 bytes, checksum: 191b8cb2f1d6177314663f065b644bed (MD5) Previous issue date: 2002
Resumo: A Curcumalonga L. originária da Índia contém curcuminóidesque além de corante, possuem atividade antioxidante com efeito antimutagênico, indicados no tratamento preventivo do câncer. O objetivo deste trabalho foi selecionar um co-solvente a ser obter extratos com alto teor de curcuminóides, e determinar suas propriedades funcionais tais como: ação antioxidante, antiproliferativa e antibacteriana. Os experimentos foram conduzidosnuma unidade de Extração Supercrítica (ESC) com extrator de leito fixo com diâmetro de 2,83x10-zme comprimento de 0,375m. Os experimentos foram realizados a 303,15K; os co-solventes testados foram etanol, isopropanol, e a mistura destes (50:50); a porcentagem de co-solvente de 6,39% a 16,11%; a vazão total do solvente variou entre 0,47xlO-skg/s a 4,45xlO-skg/s, e pressões de 200 e 300 bar. Os extratos foram analisados por COEM, CODIC, CCD e Espectrofotômetro-Uv. As propriedades funcionais foram obtidas medindo a atividade antioxidante (Monofalbmitate test), a ação antibacteriana (Microplate Alamar Blue Assay) e a ação antiproliferativa. Os resultados mostram a influência da origem na matéria-prima e do cosolvente quanto ao rendimento dos CC. O melhor co-solvente foi a mistura de etanol/isopropan l a 13,59% (massa) na vazão de 1,93x lO-skg/s, pressão de 300 bar e matéria-prima originária em São Paulo-Brasil, com rendimento de CC de 1,81%. A extração supercrítica produziu extratos com as frações volátil e pesada (CC). O resíduo do processo contém traços de CC o que poderiam imprimir propriedades funcionais no amido residual, classificando-o como amido especial.A atividade antioxidante foi de 80-95% de inibição para 3h de reação. A atividade antiproliferativa apresentou efeitos citostático e citocida a partir de 0,25 Jlg/mL e 250 J:!g/mLde extrato, respectivamente. A atividade antibacteriana iniciou na concentraçãodo extrato acima de 256 Jlg/mL(CIM). Palavras-chave:Curcuma longa L., curcuminóides,extração supercrítica,co-solvente
Abstract: The Curcuma longa L is indigenous to India. It contains curcuminoids (CC), which besides its coloring power have been reported as possessing antioxidant action such as antimutagenic effect; therefore, they are indicated for preventive cancer treatment. The objectiveofthis work was to select a co-solvent to be used with supercriticalCO2to obtain turmeric extracts with high curcuminoids content, and determine their functional properties such as antioxidant, antibacterial and antimutagenic.The experimentalruns were conducted in a SFE unit containing a fixed bed extractor with a diameter 2.83xlO-2m and length of 0.375 m. The experimental runs were performed at 303 K; co-solvent ethanol, isopropyl and their mixture (50:50) in the proportion of 6.39% to 16.11% (mass); the total solvent flow rates varied from 0.47x10-5kgls to 4.45x10-5kgls, and pressures of 200 and 300 bar. The compositions of the extracts were analyzed using GCMS, GCFID, TLC and UV spectrophotometer.The functional properties were assed measuring the antioxidant activity (Monofalbmitatetest), the action against mycobacterium (Microplate Alamar Blue Assay test), and the antiproliferative activity. The results showed that the origin of the raw material and the co-solvent influenced the yield of CC. The best process conditions were total solvent flow rate of 1.93x10-5kgls, pressure of 300 bar, mixture of the co-solvent of the ethanol/isopropyl at 13.59%(mass), and raw material grown at São Paulo-Brazil, with yield of the CC of 1.81%. SFE extracts contain both the volatile oil and heavy fraction (CC). The SFE residue contains traces of CC that can impart some functional properties to the residual starch, thus classifying it as a special starch. The antioxidant activity varied from 80 to 95% of inhibition after 3 h of reaction. The antiproliferative activity showed effects cytocide and cytostatic, for extract concentrations of 0.25 f.tglmL and 250 f.tglmL, respectively. The antibacterial activity started at an extract concentration above 256 f.tglmL (MIC).Keywords:Curcuma longa L., curcuminoids, supercritical extraction, co-solvent
Mestrado
Mestre em Engenharia de Alimentos
26
Paula, Julia Teixeira de 1988. "Obtenção de extratos de folhas de Arrabidaea chica (Humb. Bonpl.) Verlot por extração fracionada em leito fixo a alta pressão usando dióxido de carbono supercrítico, etanol e água como solventes". [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256372.
Streszczenie:
Orientadores: Fernando Antonio Cabral, Losiane Cristina PavianiDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
Made available in DSpace on 2018-08-21T23:56:25Z (GMT). No. of bitstreams: 1 Paula_JuliaTeixeirade_M.pdf: 2661007 bytes, checksum: 54793467279c439979f86fae6e09b9c5 (MD5) Previous issue date: 2013
Resumo: Extratos de folhas de Arrabidaea chica (Humb. Bonpl.) Verlot foram obtidos usando dióxido de carbono supercrítico (scCO2), etanol e água como solventes. Dois tipos de extração sequencial em leito fixo foram realizados: o primeiro tipo em três etapas, usando o scCO2 na primeira etapa, o etanol na segunda e a água na terceira, nas temperaturas de 40 °C e 50 °C e pressões de 300 bar e 400 bar; o segundo tipo em duas etapas, usando o dióxido de carbono supercrítico em uma primeira etapa, seguida de uma segunda extração com uma mistura de scCO2/etanol/água em diferentes proporções, a 40 °C e 300 bar. Para comparação, foram realizadas algumas extrações convencionais: uma extração convencional etanólica a temperatura ambiente, uma extração convencional hidroalcoólica com uma mistura de etanol, água 70:30 (v:v) a temperatura ambiente, uma extração hidroalcoólica com uma mistura de etanol, água 70:30 (v:v) a 40 °C e 300 bar e três extrações aquosas convencionais (40 °C, 50 °C e 80 °C). Todos os extratos foram caracterizados quanto ao rendimento global, às respectivas cinéticas de extração, conteúdo de compostos fenólicos totais, flavonoides totais, antocianinas monoméricas totais, carajurina e luteolina. A cromatografia líquida de alta eficiência (CLAE) foi empregada na determinação quantitativa de dois compostos selecionados: 6,7-dihidroxi-5,4'-dimetoxi flavilium (carajurina) e luteolina, além do monitoramento qualitativo dos outros dois pigmentos presentes na A. chica: pigmento (1) 6,7,3',4'- tetra-hidroxi-5-metoxi flavilium e pigmento (2) 6,7,4'- trihidroxi-5-metoxi flavilium. Nos processos de extração em leito fixo em três etapas, o rendimento total acumulado das três etapas, nas quatro condições operacionais de temperatura e pressão, variaram entre 22 % e 27 %, sendo o maior rendimento global alcançado na condição de 50 °C e 300 bar. O maior teor de compostos fenólicos totais (178,2 mg EAG/g extrato) e flavonoides totais (373,2 mg EC/ g extrato) foi obtido pelo processo realizado com a mistura 80,8 % scCO2, 19,2 % de etanol e 0 % de água. Os extratos etanólicos apresentaram maior teor de carajurina e a maior concentração de luteolina foi obtida no extrato convencional hidroalcoólico com uma mistura de etanol, água 70:30 (v:v). Na extração com scCO2 puro, obteve-se o menor rendimento de extração e foi seletiva para extrair carajurina
Abstract: Extracts from Arrabidaea chica (Humb. Bonpl.) Verlot leaves were obtained using supercritical carbon dioxide (scCO2), ethanol and water as solvents. Two types of sequential extraction were carried out in a fixed bed: the first type in three stages, using scCO2 in the first step, the ethanol in the second step and water in the third step at temperatures of 40 °C and 50 °C and pressures of 300 bar and 400 bar; the second type in two steps, using supercritical carbon dioxide in a first step, followed by a second extraction with a mixture of scCO2/ethanol/water in different proportions, at 40 °C and 300 bar. For comparison, some conventional extractions were performed: an ethanolic extract conventional at room temperature, a conventional hydroalcoholic extraction with a mixture of ethanol, water 70:30 (v: v) at room temperature, a hydroalcoholic extraction with a mixture of ethanol, water 70:30 (v: v) at 40 °C and 300 bar and three extractions conventional aqueous (40 °C, 50 °C and 80 °C). All extracts were analyzed for global yield, the respective kinetics of extraction, total phenolic compounds, total flavonoid, anthocyanins monomeric total, carajurin and luteolin. The high performance liquid chromatography (HPLC) was used for quantitative determination of two selected compounds: 6,7-dihydroxy-5, 4'-dimethoxy flavilium (carajurina) and luteolin, besides for monitoring qualitatively the other two pigments present in A. chica: pigment (1) 6,7,3 ', 4'-tetrahydroxy-5-methoxy flavilium and pigment (2) 6,7,4' - trihydroxy-5-methoxy flavilium. In the three stages extraction processes in fixed bed, the global yield of the three steps accumulated in the four operational conditions of temperature and pressure ranged between 22 % and 27 %, with the highest overall efficiency achieved in the condition of 50 °C and 300 bar. The highest content of total phenolic compounds (178.2 mg GAE / g extract) and total flavonoid (373.2 mg CE / g extract) was obtained by the process performed with the mixture scCO2 80.8 %, 19.2 % ethanol and 0 % water. The ethanol extracts showed a high level of carajurin and the highest concentration of luteolin was obtained in conventional hydroalcoholic with a mixture of ethanol, water 70:30 (v: v). In pure scCO2 extraction, the lowest extraction yield was achieved and it selective to extract carajurin
Mestrado
Engenharia de Alimentos
Mestra em Engenharia de Alimentos
27
Drunkler, Deisy Alessandra. "Estudo da estabilidade de betalaínas em diferentes solventes e em extrato de beterraba (Beta vulgaris L.) adicionado de ciclodextrinas (alfa, ß- e ÿ) e ácidos orgânicos (tânico e gálico)". Florianópolis, SC, 2001. http://repositorio.ufsc.br/xmlui/handle/123456789/79671.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias. Programa de Pós-Graduação em Ciência dos Alimentos.Made available in DSpace on 2012-10-18T06:26:00Z (GMT). No. of bitstreams: 0
A beterraba vermelha (Beta vulgaris L.) é uma importante fonte de corante natural, onde as betalaínas são a classe de pigmentos presentes neste vegetal, que compreendem betacianina (vermelha) e betaxantina (amarela). O uso deste corante na indústria alimentícia tem sido limitado em função da sua baixa estabilidade frente as condições de processamento e estocagem. Técnicas de estabilização de corantes naturais, tais como inclusão molecular e copigmentação, vem encontrando destaque em pesquisas científicas. Os objetivos deste trabalho foram avaliar o efeito de solventes extratores (água, solução aquosa de ácido cítrico 0,05% contendo 0,01% de ácido ascórbico, solução aquosa de ácido cítrico 0,1% contendo 0,1% de ácido ascórbico, solução de etanol a 50% e solução de etanol a 70%) sobre as betalaínas quanto a eficácia de extração e estabilidade; a estabilidade de betalaínas em extrato de beterraba adicionada de ciclodextrinas (a-, b- e g-CD) e ácidos orgânicos (gálico e tânico). A quantificação de betacianina e betaxantina (mg/100g de beterraba) foi realizada pelo método desenvolvido por Nilsson (1970) e a concentração de betalaína total (betacianina e betaxantina em mg/ 100g de beterraba) de acordo com o proposto por Baldini, Draetta & Sales (1986); a estabilidade foi avaliada nos solventes frente atmosfera de oxigênio/ fluxo de nitrogênio e temperatura de refrigeração (5,0 ± 1,0°C)/ ambiente (25,0 ± 1,0°C), em ausência de luz. As CDs a-, b- e g- foram adicionadas em extrato de beterraba etanólico a 70% nas concentrações de 0,925g% e 0,462g% e a estabilidade dos pigmentos avaliada frente atmosfera de oxigênio/ fluxo de nitrogênio e ambiente com presença ou ausência de luz, à temperatura ambiente. Os ácidos tânico e gálico, nas mesmas concentrações, foram adicionados em extrato de beterraba etanólico a 70% e a estabilidade avaliada nos valores de pH 5,00 ± 0,05 e 6,80 ± 0,05, à temperatura ambiente (25,0 ± 1,0 °C) e na ausência de luz. O solvente extrator que apresentou maior eficácia quanto extração de betalaínas, ambas betacianina e betaxantina, foi a água; quanto a estabilidade, a betacianina apresentou maior valor de tempo de meia vida na solução aquosa de ácido cítrico 0,05% contendo 0,01% ácido ascórbico, na temperatura de refrigeração e fluxo de nitrogênio (29342,39 ± 2763,33 h); betaxantina foi mais estável em solução etanólica a 50%, em temperatura de refrigeração e fluxo de nitrogênio (508,22 ± 17,84 h). A adição das CDs no extrato de beterraba etanólico a 70% (soluções aquosas favoreceram o desenvolvimento fúngico), nas concentrações e condições avaliadas, não promoveram aumento de estabilidade das betalaínas. Os ácidos tânico e gálico promoveram aumento significativo da estabilidade do pigmento betacianina somente no pH de 5,00 ± 0,05, neste valor de pH e para as duas concentrações avaliadas os tratamentos com ácido tânico apresentaram melhores resultados. Observou-se diferenças significativas quanto extração e estabilidade de betalaínas; as ciclodextrinas não foram eficazes no aumento da estabilidade destes pigmentos; por sua vez ácidos tânico e gálico aumentaram a estabilidade da betacianina.
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Diniz, Tábata Táyara Garmus 1988. "Obtenção de extratos de folhas de pitanga (Eugenia uniflora L.) e de alecrim-pimenta (Lippia sidoides Cham.) por extração sequencial em leito fixo usando CO2 supercrítico, etanol e água como solventes". [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256371.
Streszczenie:
Orientadores: Fernando Antonio Cabral, Losiane Cristina PavianiDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Esse trabalho objetivou, através da combinação de processos de extração, a obtenção de extratos naturais a partir de folhas de pitanga (Eugenia uniflora L.) e de folhas de alecrim-pimenta (Lippia sidoides Cham.). Os extratos foram obtidos por extração sequencial em leito fixo a 60 ºC e 400 bar, primeiro por extração com dióxido de carbono supercrítico (scCO2), seguido por extração com etanol em uma segunda etapa e por último, extração com água (terceira etapa). Curvas de extração (rendimento de extrato em função da massa de solvente) foram obtidas no intuito de se avaliar o desempenho da extração quanto ao rendimento em função do tipo de solvente. Todos os extratos foram avaliados quanto ao teor de fenóis e flavonoides totais e a fração volátil obtida na primeira etapa com scCO2 foi avaliada quanto ao seu perfil químico por cromatografia gasosa acoplada a espectrometria de massas (GC-EM). Para efeito de comparação, mais dois tipos de extratos etanólicos e aquosos foram obtidos: 1) Extratos em etapa única a partir das folhas, com etanol e com água em leito fixo a 60 °C e 400 bar sem prévia extração com scCO2 e 2) Extratos convencionais utilizando um sistema a baixa pressão e 60 ºC. A análise dos resultados mostrou que o caráter do solvente empregado influenciou significativamente no processo de obtenção dos extratos, pois o rendimento apresentou tendência de aumento com o aumento da polaridade do solvente, sendo os extratos aquosos os de maior rendimento, seguidos dos etanólicos e por último os supercríticos. O estudo apontou o processo de extração sequencial (em três etapas) como o mais eficaz em termos de rendimento global de extração e de fenóis e flavonoides totais para Eugenia uniflora. O extrato obtido com etanol (60 ºC e 400 bar) após extração supercrítica e o extrato obtido com scCO2 apresentaram as maiores concentrações de fenóis e flavonoides totais, respectivamente, dentre todos os extratos obtidos das folhas de E. uniflora L. Na matriz Lippia sidoides Cham., o processo de extração etanólica a 60 ºC e 400 bar em etapa única permitiu obter extratos mais concentrados em fenóis e flavonóis e o melhor rendimento de flavonoides totais. Os resultados para o rendimento de compostos fenólicos do alecrim-pimenta aponta a extração sequencial como a mais eficiente. A influência da extração supercrítica prévia foi diferente dependendo da matriz vegetal estudada. O scCO2 como primeiro solvente de extração permitiu obter extratos etanólicos e aquosos mais concentrados em compostos fenólicos para pitanga
Abstract: The objective of this study was to obtain natural extracts from leaves of pitanga (Eugenia uniflora L.) and pepper-rosmarin (Lippia sidoides Cham.) with the combination of different sequential extraction techniques. The extracts were obtained by sequential extraction in fixed bed (60 °C and 400 bar), first by extraction with supercritical carbon dioxide (scCO2), followed by extraction with ethanol in a second step and finally extracted with water in a third step. Extraction curves (yield of extracts by the mass of solvent) were obtained in order to evaluate the performance of the extraction yield due to the type of solvent. All extracts were evaluated for their content of total phenols and flavonoids and the more volatile fraction obtained in the first step with scCO2 was evaluated for its chemical profile by gas chromatography coupled to mass spectrometry (GC-MS). For comparison, two types of ethanol and aqueous extracts were obtained: 1) single-step extracts from the leaves with ethanol and water in the fixed bed at 60 °C and 400 bar without prior extraction with scCO2 and 2) extracts using a conventional low pressure system and 60 °C. The results showed that the nature of the solvent employed strongly influenced the process of obtaining extracts, as the yield showed a tendency to increase with increasing polarity of the solvent. The aqueous extracts showed the highest yield, followed by ethanol and finally the supercritical The study pointed out the process of sequential extraction (three-step) as the most effective in terms of global extraction yield and total phenols and flavonoids for Eugenia uniflora. The extract obtained with ethanol (60 °C and 400 bar) after supercritical extraction and the extract obtained with scCO2 were those with the highest concentrations of total phenols and flavonoids, respectively, among all the extracts obtained from the leaves of E. uniflora L. At Lippia sidoides Cham. matrix, the process of single-step ethanolic extraction at 60 °C and 400 bar obtained more concentrated yields in phenols and flavonols and the best yield of total flavonoids. The results for the yield of phenolic compounds from pepper-rosmarin indicate the sequential extraction as the most efficient process. The influence of prior supercritical extraction was different according to plant matrix studied. The scCO2 as the first extraction step yielded ethanolic and aqueous extracts more concentrated in phenolic compounds for E. uniflora
Mestrado
Engenharia de Alimentos
Mestra em Engenharia de Alimentos
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Elsayed, Nada H. "Leaching of active ingredients from blueberries and cranberries using supercritical carbon dioxide and ethanol as an entrainer and analyzing using GC/MS". [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0002933.
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Vernes, Léa. "Mise au point d’un procédé innovant d’éco-extraction assisté par ultrasons d’ingrédients alimentaires à partir de spiruline et transposition à l’échelle industrielle Application of a green sono-process to extract proteins from spirulina. Mechanism, optimization, modeling, and industrial prospects Green solvents for sample preparation in analytical chemistry. Phycocyanin from Arthrospira platensis. Production, Extraction and Analysis Ultrasound and microwaves as useful tools for solid-liquid extraction Bio-refinery concept as a key for sustainable future to green chemistry – The case of microalgae". Thesis, Avignon, 2019. http://www.theses.fr/2019AVIG0273.
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Les microalgues sont l’une des ressources renouvelables les plus prometteuses pouvant constituer une alimentation durable future. Grâce à leur diversité de métabolisme, ces microorganismes sont capables de synthétiser une vaste gamme de composés d’intérêt à haute valeur nutritionnelle. Cependant, leur consommation reste limitée du fait de leurs caractéristiques organoleptiques intrinsèques peu attrayantes. Afin de répondre à cette problématique et de lever les verrous, les travaux de cette thèse ont porté sur la mise au point d’un procédé de production d’ingrédient alimentaire à partir de spiruline.Une méthode verte et innovante faisant intervenir la technologie ultrasonore pour l'extraction de protéines à partir d'Arthrospira platensis a été proposée dans une première partie. Il s’agit de la manothermosonication (MTS). Le recours à un plan d’expérience a permis d’optimiser les paramètres d’extraction ; et une modélisation mathématique ainsi que des investigations microscopiques ont mené à une compréhension des phénomènes de transfert de masse d’une part et des effets structurels des ultrasons sur les filaments de spiruline d’autre part. Selon les résultats expérimentaux, la MTS a permis d'obtenir 229 % de protéines en plus (28,42 ± 1,15 g / 100 g MS) par rapport au procédé classique sans ultrasons (8,63 ± 1,15 g / 100 g MS). Avec 28,42 g de protéines pour 100 g de spiruline dans l'extrait, un taux de récupération des protéines de 50 % a été atteint en 6 minutes effectives avec un procédé MTS continu. Partant de ces résultats prometteurs, des pistes d’extrapolation ont été étudiées afin de proposer des outils d’aide à la décision pour l’industrialisation du procédé. Ainsi une procédure d’analyse des risques (HACCP & HAZOP), une étude de coût ainsi que l’impact environnemental du procédé ont été développés dans une seconde partie de ces travaux. Enfin, des voies de valorisation des co-produits d’extraction ont été présentées dans une approche de bioraffinerieMicroalgae are one of the most promising renewable resource for future sustainable food. Thanks to their diversity of metabolism, these microorganisms can synthesize a wide range of compounds of interest with high nutritional value. However, their consumption remains limited because of their intrinsic organoleptic characteristics unattractive. To tackle this problem and to overcome these barriers, this thesis was focused on the development of a production process of food ingredient from spirulina.A green and innovative method using ultrasonic technology for the extraction of proteins from Arthrospira platensis was proposed in a first part. This is the manothermosonication (MTS). The use of an experimental plan made it possible to optimize extraction parameters; and mathematical modeling and microscopic investigations led to an understanding of the mass transfer phenomena on the one hand, and the structural effects of ultrasound on spirulina filaments on the other hand. According to the experimental results, MTS allowed to obtain 229 % more proteins (28.42 ± 1.15 g / 100 g DW) compared to the conventional method without ultrasound (8.63 ± 1.15 g / 100 g DW). With 28.42 g of protein per 100 g of spirulina in the extract, a protein recovery rate of 50% was achieved in 6 minutes with a continuous MTS process. Based on these promising results, extrapolation tracks have been studied in order to propose decision support tools for process industrialization. Thus, a risk analysis procedure (HACCP & HAZOP), a cost study as well as the environmental impact of the process were developed in a second part of this work. Lastly, ways of exploiting by-products have been presented in a biorefinery approach
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Lukhele, Sindiswa Thandeka. "Crude extracts of solvents isolated from cannabis sativa plant extracts inhibit growth and induce apoptosis in cervical cancer cells". Thesis, 2016. http://hdl.handle.net/10539/20361.
Streszczenie:
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Masters in Science.
December 2015Cervical cancer remains a global health related issue among females of Sub-Saharan Africa, with over half a million new cases reported each year. Different therapeutic regimens have been suggested in various regions of Africa, however, over a quarter of a million women die of cervical cancer, annually. This makes it the most lethal cancer amongst black women in this area, and makes it important to search for new effective therapeutic drugs through screening of medicinal plant extracts used by many in Sub-Saharan Africa as potential anti-cervical cancer agents. The aim of this study was to evaluate the anti-proliferative effects of Cannabis sativa extracts and its isolate, cannabidiol on cervical cancer cell lines HeLa, SiHa, and ME-180. To achieve our aim, phytochemical screening, MTT assay, cell growth analysis, flow cytometry, morphology analysis, Western blot, caspase 3/7 assay, and ATP measurement assay were conducted were conducted. Results obtained indicate that both plant extracts induced cell death at an IC50 of 50 – 100μg/ml and the Inhibition of cell growth was cell line dependent. Flow cytometry confirmed that, with or without cell cycle arrest, the type of induced cell death was apoptosis. Cannabis sativa extracts led to the up-regulation of apoptosis proteins (p53, Bax, caspase-3, and caspase-9) and the down regulation of anti-apoptosis proteins (Bcl-2 and RBBP6), signalling the execution of apoptosis. Apoptosis induction was further confirmed by morphological changes, an increase in Caspase 3/7 and a decrease in the ATP levels. In conclusion, this data implies Cannabis sativa crude extracts has the potential to inhibit growth and induce apoptosis in cervical cancer cell lines, which may be due to the presence of cannabidiol. Key words: Apoptosis, cervical cancer cells, cannabidiol, and Cannabis sativa extracts
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Jan, Kuo-Ching, i 詹國靖. "Study on the antioxidative activities of extracts from sesame meal with different solvents". Thesis, 2001. http://ndltd.ncl.edu.tw/handle/57095274646679982717.
Streszczenie:
碩士國立臺灣大學
園藝學研究所
89
ound hydrophobic lignans (sesamolin, pinoresinol, sesaminol, sesamin) and hydrophilic lignan glycosides. Most of the sesame oil is produced by roasting and pressing. After high temperature roasting, the sesame meal appeared bitter taste and its protein was highly denatured. Therefore, the sesame meal is generally used as feeds or fertilizers. The purpose of this study was to extract the sesame meal in supercritical carbon dioxide (SC-CO2) and different solvents. The extracted after various solvents treatment were analyzed to determine the optimum processing condition.We hope we can increase the amount of functional components in sesame meal to enhance the utilization of sesame meal. The sesame meal was extracted with five solvents (n-hexane, ethyl acetate, ethanol, methanol and water). Ethanol extracts exhibited strong DPPH( 2,2-diphenyl- 1-picrylhydrazyl) free radical scavenging effect. When various concentration ethanol extract, 80% ethanol crude extracts showed good antioxidative activity toward DPPH free radical scavenging effect and inhibition of lipide oxidation(88.51%, 73.25%). Crude extracts (80% ethanol) have significantly content on brown index and sesaminol triglucoside content. To investigate the effect of an entrainer on SC-CO2. Using ethanol as an entrainer on SC-CO2 than added to the sample would give strong DPPH free radical scavenging effect. At constant temperature 50 to 70℃, decreased the amount SC-CO2 (25-50NL), raising temperature increased sesamol contents. At 70℃/fraction 2 have high content (0.452 mg/g crude extract). Under the operation temperature from 50℃ to 70℃, the DPPH free radical scavenging effect were decreased with increasing temperature. At 50℃/fraction 4 showed better DPPH free radical scavenging effect(77.43%), crude extracts have significantly content on brown index and total phenolics content. At constant temperature (50℃), pressure (4000psi) and the amount of ethanol (10mol%) , fraction 4 showed the largest sesamol contents (0.134 mg/crude extract) and total phenolics content(0.229 mg/crude extract). The crude extracts showed good antioxidative activity toward DPPH free radical scavenging effect (77.43%) and inhibition of lipide oxidation(77.73%).The incresment of antioxidative activity of crude extract of lignan glycosides was probably due to the total phenolics contents and maillard reaction products formed during roasting process.
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Vieira, Vanessa Ariana Azevedo. "Using alternative solvents for the extraction of bioactive compounds from Juglans regia L". Doctoral thesis, 2019. http://hdl.handle.net/10773/30124.
Streszczenie:
Plants and its residues resulting from the agroforest and food industries are
potential sources of bioactive compounds. In this context, it is of great importance
to carry out the chemical and biochemical characterization of the extracts of
various plant materials evaluating their bioactivity in different dimensions
(antioxidant, anti-inflammatory, antimicrobial, anti-tumour, among others), as
well as to obtain those extracts by designing more efficient, sustainable and safer
processes.
In particular, phenolic compounds represent the fraction of secondary
metabolites of plants most widely extracted and recognized for their abundance
and bioactivity. In this thesis, the phytochemical profile and bioactivity of two
plant matrices that stand out as natural sources of this type of compounds were
studied: the leaves of walnut trees and walnut green husks. Thus, after the
chemical and bioactive characterization of the biomass, the extraction process
of phenolic compounds was optimized, applying an experimental design assisted
by response surface methodology, using ethanol as solvent in a first stage. After,
alternative solvents to volatile organic solvents were studied, such as alkanediols
and eutectic solvents based on choline chloride and carboxylic acids or
alkanediols. In the latter case, the extracts incorporated in the solvent may be
used as components of formulations with potential application in the food,
pharmaceutical or cosmetic industries.
Finally, the choice of solvents for the extraction and purification of phenolic
compounds is generally performed empirically, as scarce information on their
solubility in common organic solvents is available. Therefore, it was considered
appropriate to study the solubility of three arotimatic acids of great relevance in
the biorefinery context. The thermodynamic modelling of the solid-liquid
equilibrium of these mixtures was performed using the NRTL-SAC model
(Nonrandom Two-Liquid Segment Activity Coefficient) and the Abraham's
solvation model, whose semi-predictive character will simplify the preliminary
selection of solvents for a given process.As plantas e os seus resíduos resultantes das indústrias agro-florestal e alimentar são uma potencial fonte de compostos bioativos. Neste contexto, revela-se de grande importância a caracterização química e bioquímica dos extratos de diversas matrizes vegetais avaliando a sua bioatividade em várias dimensões (antioxidante, anti-inflamatória, antimicrobiana, antitumoral, entre outras), bem como a obtenção desses extratos através de processos mais eficientes, sustentáveis e seguros. Em particular, os compostos fenólicos representam a fração de metabolitos secundários de plantas mais amplamente extraída e reconhecida pela sua abundância e bioatividade. Nesta tese, estudou-se o perfil fitoquímico e a bioatividade de duas matrizes vegetais que se destacam como fontes naturais deste tipo de compostos: as folhas da nogueira e os mesocarpos da noz. Assim, após a caracterização química e bioativa da biomassa, otimizou-se o processo de extração de compostos fenólicos, aplicando um planeamento experimental e a metodologia de superfície de resposta, e utilizando etanol como solvente numa primeira fase. Depois, estudaram-se solventes alternativos aos solventes orgânicos voláteis, tais como alcanodióis e solventes eutécticos baseados em cloreto de colina e ácidos carboxílicos ou alcanodióis. Neste último caso, os extratos inseridos no solvente poderão ser utilizados como componentes de formulações com potencial aplicação nas indústrias alimentar, farmacêutica ou cosmética. Finalmente, a escolha dos solventes de extração e purificação de compostos fenólicos é realizada, em geral, de forma empírica, existindo pouca informação sobre a sua solubilidade em solventes orgânicos comuns. Neste sentido, considerou-se oportuno estudar a solubilidade de três ácidos aromáticosde enorme relevância no contexto das biorrefinarias. A modelação termodinâmica do equilíbrio sólido-líquido destas misturas foi efetuada com o modelo NRTLSAC (Nonrandom Two-Liquid Segment Activity Coefficient) e o modelo de solvatação de Abraham, cujo carácter semi-preditivo permitirá simplificar a seleção preliminar de solventes para um determinado processo.
Programa Doutoral em Engenharia Química
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Huang, Ching-Ju, i 黃敬如. "Antioxidant Activity and Anti-inflammatory effect of Kumquat’s Extracts by Successive Extraction with Different Solvents". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/60799891909407143809.
Streszczenie:
碩士國立宜蘭大學
食品科學系碩士班
97
The present study was to evaluate the bioactive related compounds, the antioxidant activity and anti-inflammatory effect of peel and pulp in two kumquats, Fortunella margarita (FM) and Citrofortunella mitis(CM). In order to evaluate the antioxidant activity of sample, a new method with 2’deoxyguanosine instead of ribose was developed to investigate the scavenging effect of hydroxyl radical by HPLC chromatography. The successive extractions followed by hexane, ethyl acetate, methanol and water were collected separately and then subjected to the determinations. The results showed that the optimal processing conditions with 2’deoxyguanosine for scavenging effect of hydroxyl radical were in 0.2 M ferrous iron, 20% hydrogen peroxide, 0.3 M EDTA and reacted for 60 min. The higher scavenging effect was observed in water and methanol extract from the peel of Fortunella margarita. In the superoxide anion scavenging activity, the antioxidant activity of methanol and water extracts were also better than hexane and ethyl acetate extract. The antioxidant activity of peel was obviously higher than its of pulp. This implied that the polar substances in peel provided the major antioxidant activity in Fortunella margarita (FM) and Citrofortunella mitis(CM). The ethyl acetate extract of FM’s and CM’s peel contained the highest inhibitory activity against COX-2. However, the EVIC50 of methanol extract from peel showed the best inhibitory activity. A similar data were observed that the ethyl acetate extract of peel inhibited 15-LOX activity effectively. The best EVIC50 related to 15-LOX activity were ethyl acetate extract of CM. Collectively, the ethyl acetate extract of CM peel contained the highest anti- inflammatory activity. The contents of total phenol, total flavonoids, total caroteneoids and ascorbic acid in peel were higher than in pulp, but total contents were no difference between FM and CM. The identified flavonoids in FM were naringin, neohesperidin and nobiletin. However, five major flavonoids were observed in CM, such as naringin, hesperidin, neohesperidin, nobiletin and diosmetin. During drying processing, the higher drying temperature, the lower COX-2 inhibitory activity was found in the ethyl acetate extract from CM peel. The inhibited activity of COX-2 in ethyl acetate extract from peel, heated at 150℃, was 2 times better than peel, treated under frozen drying. In the inhibitory 15-LOX activity assay, the activity of ethyl acetate extract decreased, while the drying temperature increased. Collectively, the extracts of ethyl acetate from peel had better anti-inflammatory effect than the extracts of polar solvents. On the contrary, the extract of methanol and water had better antioxidant activity than the extracts of non polar solvents. These might probably due to the higher total phenolic content in methanol and water extracts. And the higher flavonoids content in ethyl acetate extract might play an important role in anti-inflammatory effect.
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Besrour, Nermine. "Development of semi-solid formulations containing Juglans regia L. leaves extracts for topical application". Master's thesis, 2019. http://hdl.handle.net/10198/22988.
Streszczenie:
Mestrado de dupla diplomação com a Université Libre de TunisThe leaves of walnut trees (Juglans regia L.) stand out as a rich source of phenolic compounds and other phytochemicals. Because of that, their extracts find application as traditional herbal medicinal products and can also be valorized as potential bioactive ingredients in the cosmeceutical and food areas, among others. In this context, the main objective of this thesis is to develop a semi-solid formulation for topical use containing Juglans regia extracts and, then, to characterize and analyze the bioactive properties and stability of the final formulation. After obtaining the extract using both hydroethanolic and 1,2-propanediol mixtures, a series of bioactivity studies such as antioxidant, cytotoxic, anti-inflammatory, antimicrobial, anti-tyrosinase and photostability were carried out. The hydroethanolic extracts were more efficient than the propanediol extract in the anti-tyrosinase, antioxidant, and anti-inflammatory assays. In the antimicrobial assay both extracts showed similar microbial properties. Both extracts were found to be rich sources of phenolic compounds, being 3-O-caffeoylquinic acid, quercetin-O-pentoside, taxifolin O-pentoside isomer, quercetin 3-O-glucoside, and 3-p-coumaroylquinic acid, the most abundant compounds. The propanediol and hydroethanolic extracts were incorporated in a base cream to have the final formulation for topical application. The stability of the final formulation was studied according to the following parameters: pH, color, phenolic compounds, and antioxidant activity. After incorporation into the base cream, the hydroethanolic extract preserved its phenolic compounds content over time at different storage conditions. Regarding the formulation containing propanediol extract, quercetin 3-O-glucoside and traces of other compounds were identified due to the small amount of incorporated extract. Both final formulations also presented antioxidant activity and a pH ranging from 3.8 and 4.7 which is compatible within the range of normal skin. These preliminary results suggest the potential use of J. regia extracts as a source of bioactive compounds for further incorporation into skin care products. Further work should be carried out to assess a longer term stability, safety and toxicity of these extracts.
Les feuilles des noyers (Juglans regia L.) se distinguent comme une riche source de composés phénoliques et d'autres composés phytochimiques. Pour cette raison, leurs extraits ont des applications en tant que produits médicinaux traditionnels à base de plantes et peuvent également être valorisés comme ingrédients bioactifs potentiels dans les domaines cosméceutique et alimentaire. Dans ce contexte, l'objectif principal de cette thèse est de développer une formulation semi-solide à usage topique contenant des extraits de Juglans regia et ensuite de la caractériser et d'analyser les propriétés bioactives et la stabilité de la formulation finale. Après avoir obtenu l'extrait en utilisant hydroéthanol et de 1,2-propanediol, une série d'études de bioactivité telles qu'antioxidant, cytotoxique, anti-inflammatoire, antimicrobien, anti-tyrosinase et photostabilité ont été réalisées. Les extraits hydroéthanoliques étaient plus efficaces que l'extrait de propanediol dans les dosages anti-tyrosinase, antioxydant et anti-inflammatoire. Dans le test antimicrobien, les deux extraits ont montré des propriétés microbiennes similaires. Les deux extraits se sont avérés être de riches sources de composés phénoliques, à savoir l'acide 3-O-caféoylquinique, la quercétine-O-pentoside, l'isomère de la taxifoline O-pentoside, la quercétine 3-O-glucoside et l'acide 3-p-coumaroylquinique, les plus abondants composés. Les extraits de propanediol et d'hydroéthanol ont été incorporés dans une crème de base pour avoir la formulation finale pour application topique. La stabilité de la formulation finale a été étudiée en fonction des paramètres suivants: pH, couleur, composés phénoliques et activité antioxydante. Après incorporation dans la crème de base, l'extrait hydroéthanolique a conservé sa teneur en composés phénoliques au fil du temps dans différentes conditions de stockage tandis que le propanediol ne conservait que la quercétine 3-O-glucoside et des traces d'autres composés en raison de la quantité incorporée et du manque d'optimisation d’extraction avec ce solvant. Les deux formulations finales ont montré une activité antioxidante et également un pH compris entre 3,8 et 4,7 qui montrent aussi une bonne photostabilité. la lumiére des formulations finales augmentait avec le temps ce qui est meilleur pour l'aspect de la crème. Ces résultats préliminaires suggèrent l'utilisation potentielle des extraits de J. regia comme source d'extraits bioactifs pour le développement de produits de soins de la peau. Des travaux supplémentaires devraient être menés pour évaluer la stabilité, la sécurité et la toxicité à plus long terme de ces extraits.
As folhas das nogueiras (Juglans regia L.) destacam-se como uma fonte rica em compostos fenólicos e outros fitoquímicos. Por essa razão, os seus extratos encontram aplicação na medicina tradicional, podendo também ser valorizados como potenciais ingredientes bioativos nas áreas cosmecêutica e alimentar, entre outras. Nesse contexto, o principal objetivo desta tese é desenvolver uma formulação semissólida para uso tópico contendo extratos de Juglans regia e, depois, caracterizar e analisar as propriedades bioativas e a estabilidade da formulação final. Após a obtenção do extrato utilizando misturas de água e etanol, e 1,2-propanodiol, realizaram-se diversos estudos de bioatividade tais como antioxidante, citotoxicidade, anti-inflamatória, antimicrobiana, anti-tirosinase e fotoestabilidade. Os extratos hidroetanólicos foram mais eficientes que o extrato de propanodiol nos ensaios de atividade anti-tirosinase, antioxidante e anti-inflamatória. No ensaio antimicrobiano, ambos os extratos apresentaram propriedades semelhantes. Ambos os extratos foram considerados fontes ricas em compostos fenólicos, sendo os compostos mais abundantes o ácido 3-O-cafeoilquínico, a quercetina-O-pentosídeo, o isómero O-pentosídeo de taxifolina, a quercetina 3-O-glucosídeo e o ácido 3-p-coumaroilquínico. Os extratos obtidos foram incorporados num creme base comercial para obtenção de uma formulação final para aplicação tópica. A estabilidade da formulação foi estudada de acordo com os seguintes parâmetros: pH, cor, compostos fenólicos e atividade antioxidante. Após a incorporação no creme base, o extrato hidroetanólico preservou o seu conteúdo em compostos fenólicos ao longo do tempo, em diferentes condições de armazenamento. Relativamente à formulação contendo o extrato em propanodiol, apenas se detetou quercetina 3-O-glucósideo e vestígios de outros compostos devido à pequena quantidade de extrato incorporado. As duas formulações finais apresentaram também atividade antioxidante e valores de pH entre 3,8 e 4,7 o que é compatível com a gama de pH normal da pele. Estes resultados preliminares sugerem o potencial uso dos extratos de J. regia como fonte de compostos bioativos para o desenvolvimento de produtos para a pele. Estudos adicionais deverão ser realizados para avaliar a estabilidade a longo prazo, a segurança e a toxicidade destes extratos.
This work was developed within the scope of the project AllNat – “Using natural deep eutectic solvents for the extraction of bioactive compounds from plant material” (reference POCI-01-0145-FEDER-030463, PTDC/EQU-EPQ/30463/2017), funded by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI), Portugal 2020 and by national funds through Foundation for Science and Technology (FCT/MCTES).
36
Chen, Yen-Chang, i 陳彥璋. "Effect of ultrasonic extraction and extraction solvents on the antioxidant activities of garlic skin extracts and its application to pork patties". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/87428443946792258547.
Streszczenie:
碩士國立中興大學
動物科學系所
101
Sanitation and safety of foods have become great concerns for consumers. Synthetic antioxidant, such as BHA (butylated hydroxyanisole) and BHT (butylated hydroxytoluene) have been doubted for their safety even though they exhibit good antioxidant activities. This concern has led to a great interest in development of natural antioxidants which might at least partially replace synthetic ones. Garlic (Allium sativum) has been used universally as a flavoring ingredient, and materials of functional food and traditional medicine. Previous studies have shown that garlic contains some phenolic compounds and sulfur compounds which contribute to their antioxidant activities. However, garlic skin, an inedible part and a waste which produced during manufacturing, has not been studied intensely for their uses. Many studies which regarding the re-utilization of agricultural by-products have been conducted due to their functional components. Ultrasonic extraction has gained much attention due to its higher extraction efficiency as well as shorter extraction time when compared to the conventionally maceration methods. Furthermore, it creates less impact on the phenolic compounds when compared to other extraction methods. Therefore, the objectives of this study were (1) to investigate the effect of ultrasonic extraction and extraction solvents on the antioxidant properties of garlic skin extracts and (2) to evaluate the qualities of fresh and pre-cooked pork patties which were added with garlic skin extracts during refrigerated storage. The result showed that the water extracts exhibited higher yield, while the ethanol extracts showed higher total phenolic contents, DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging activity, ferrous ion chelating ability and reducing power. Ethanol extracts also showed higher yields of phenolic compounds obtained form the dry materials. On the other hand, garlic skins which were ultrasonically extracted for 15 min had equivalent or higher total phenolic contents than the ones conventionally extracted for 12 to 24 h. However, the DPPH scavenging activity of ultrasonic extracts was similar to the treatments macerated for 1.5 to 3 h as using water as an extraction solvent. Therefore, ethanol extracts which were ultrasonically extracted for 15 min and conventionally extracted for 12 h were chosen to be added for the further study. In the 2nd part of study, addition of garlic skin ethanol extract decreased the L* value (lightness) and retarded the decreasing of a* value (redness) of fresh and pre-cooked patties during storage at 4 °C. For the lipid oxidation evaluation, CD (conjugated dienes) and TBARS (2-thiobarbituric acid reactive substances) values of the fresh patties were increased during storage, whereas the both values of pre-cooked were decreased after storage for 9 days. Addition of extracts significantly retarded the increases of CD and TBARS values for fresh and pre-cooked patties. The treatments with addition of extracts showed lower rancid flavor and higher sensory acceptance than controls during refrigerated storage. In conclusion, the ethanol garlic skin ultrasonic extracts had equivalent antioxidant activities than that of the treatments conventionally extracted for long time. Addition of 0.1% extract could retard lipid oxidation and sensory deterioration effectively and improve overall acceptance of meat products. Not only dramatically increase the uses of garlic skin, the results of this study clearly demonstrated the potent development of natural antioxidant and application in meat and other foods in the future.
37
Luo, Man-Li, i 羅曼莉. "Evaluation of antibacterial activity of Toona sinensis and Houttuynia cordata extracts using different solvents and their application in Taiwanese style sausage". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/60936094771258842560.
Streszczenie:
碩士國立中興大學
動物科學系所
100
Abstract Taiwanese style sausage is a semi-dry sausage made with the larger particle size of ground pork curing with backfat, high sugar content, rice wine and some spices, which produces a unique aroma after curing. However, the shelf life of this product is a short time due to high sugar content, low temperature and short time for drying and makes it susceptible to bacterial growth. Therefore, the utilization of extracts of Toona sinensis or Houttuynia cordata in Taiwanese style sausage to inhibit bacteria and prolong the shelf life during storage at high refrigerated temperature (15°C) was the purpose of this research. In experiment I, total flavonoids and total phenolics contents of both herb extracts were increased (p<0.05) with the percentage herbs of solutions, T. sinensis extracted with ethanol (Te) had higher total flavonoids and total phenolics contents than that of extracted with water (Tw) and H. cordata extracted with ethanol (Hc). In experiment II, the residual of total phenolics contents, the scavenging capacity of DPPH radical and the chelating Fe2+ ability of all groups were decreased (p<0.05) with heating time and temperature increase, Te had higher the residual of total phenolics contents and better scavenging capacity than Tw and Hc when heated at the same temperature and time. However, Tw had better chelating ability than TE and Hc. In Experiment III, Te showed the best inhibition (p<0.05) on the growth of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Lactobacillus acidophilus, but Tw only had slight inhibition on the growth of S. aureus and L. acidophilus, however, Hc didn’t have antibacterial activity on the growth of all selected bacteria in this study. In experiment IV, the total plate count, anaerobic plate count, lactic acid bacteria count, mold and yeast count and VBN value of all treatments increased (p<0.05) with storage time, the sausage treated with 250 ppm T. sinensis (Te250) and 125 ppm T. sinensis (Te125) showed the lower bacteria count and VBN value during storage and the results were similar to the results of NaL. However, sausage treated with potassium sorbate (KS), 125 ppm H. cordata (Hc125) and 250 ppm H. cordata (Hc250) had higher bacteria count and VBN value. Sausages treated with NaL, Te125 and Te250 had higher pH values than that of Hc125 and Hc250 and KS during storage at 15°C. The L*, a* and b*, color, flavor and overall acceptance of the sensory score of all treatment decreased with storage time but off-odor of all treatments was increased with storage time. In conclusion, extracts of Toona sinensis possessed high total flavonoids and total phenolics contents and also showed high antibacterial ability, especially extract of T. sinensis with ethanol. The application of herbs extracts in Taiwanese style sausage and stored at higher refrigerated temperature (15°C), sausages treated with T. sinensis extracts showed better antibacterial activity than that of Houttuynia cordata and potassium sorbate and the same as sodium lactate in the study. Therefore, extracts of T. sinensis would be suitable to replace sodium lactate or potassium sorbate in Taiwanese style sausage for inhibiting the growth of bacteria in the future.
38
Chammakhi, Yosra. "Valorization of Aloe vera leaf rind extracts through partition studies and the development of a cosmetic formulation". Master's thesis, 2022. http://hdl.handle.net/10198/25148.
Streszczenie:
Mestrado em Engenharia Quimica IPB-ESTGAloe vera (Aloe barbadensis Mill.) is a succulent xerophytic medicinal plant that has assumed, in the last decades, great importance in the industrial sector due to its bioactive properties, which is why it is used in the development of cosmeceuticals, functional foods and food supplements. In this work, the focus is on the green rind of the Aloe vera leaf, which is usually considered a waste part of the plant. The main objectives were to obtain the partition coefficients of the main anthrones and chromones present in the extracts to support the design of fractionation processes using centrifugal partition chromatography (CPC), to develop a semi-solid formulation for topical use containing glycerol (G), propylene glycol (PG) and water (W) extracts, and characterize the bioactive properties and shelf stability of the final formulation. The chemical characterization of aloesin-rich extracts showed that the highest content of phenolic compounds was detected in W extract and the most abundant compounds were aloeresin B and aloin A. The G extract presented the best DPPH radical scavenging activity followed by W and PG extracts. The G and W extracts were the most stable when exposed to UVA and UVB radiation at different tested skin pH (3-6). Also, the three extracts had a MIC = 5 mg/mL against the bacterial pathogen of the skin Enterococcus faecalis, which can be beneficial for application in the cosmeceutical field. Antibacterial results showed that the PG extract presented broad spectrum antibacterial activity against Gram-positive and Gram-negative bacteria. PG and G extracts also presented anti-inflammatory activity. After incorporation of the extracts in a base cream, the final formulations presented higher antioxidant activity compared to the base cream (control). The antioxidant activity was evaluated at different storage condition along time and the results showed that the extracts retained its functionality (antioxidant capacity) after being incorporated in the base cream. The colour and pH analysis showed that the final formulations had good physicochemical stability when stored during 14 days at different temperatures. Finally, regarding the partition coefficients studies of the main anthrones and chromones present in the extracts, depending on the target compounds, very promising results were obtained using binary or ternary mixtures of the biphasic system water + butan-1-ol + ethyl acetate.
A Aloe vera (Aloe barbadensis Mill.) é uma planta medicinal xerofítica suculenta que tem assumido, nas últimas décadas, grande importância no setor industrial devido às suas propriedades bioativas, razão pela qual é utilizada no desenvolvimento de cosmecêuticos, alimentos funcionais e suplemento alimentares. Neste trabalho, o foco está na casca verde da folha de Aloe vera, que normalmente é considerada um resíduo da planta. Os principais objetivos foram obter os coeficientes de partição das principais antronas e cromonas presentes nos extratos para suportar o projeto de processos de fracionamento por cromatografia de partição centrífuga, desenvolver uma formulação semissólida para aplicação tópica contendo extratos de glicerol (G), propileno glicol (PG) e água (W), e caracterizar as propriedades bioativas e a estabilidade da formulação final. A caracterização química dos extratos ricos em aloesina mostrou que o maior teor de compostos fenólicos foi detetado no extrato W e os compostos mais abundantes foram aloeresina B e aloína A. O extrato G apresentou a melhor atividade sequestradora de radicais DPPH, seguido pelos extratos W e PG. Os extratos G e W foram os mais estáveis quando expostos à radiação UVA e UVB nos diferentes pH de pele testados (3-6). Além disso, os três extratos apresentaram CIM = 5 mg/mL contra o patógeno bacteriano da pele Enterococcus faecalis, o que poderá ser benéfico para aplicação na área cosmecêutica. Os resultados antibacterianos mostraram que o extrato de PG apresentou atividade antibacteriana de largo espectro contra bactérias Gram-positivas e Gram-negativas. Os extratos de PG e G também apresentaram atividade anti-inflamatória. Após incorporação dos extratos no creme base, as formulações finais apresentaram maior atividade antioxidante em relação ao creme base (controlo). A atividade antioxidante foi avaliada em diferentes condições de armazenamento ao longo do tempo e os resultados mostraram que os extratos retiveram a sua funcionalidade (capacidade antioxidante) após incorporação no creme base. As análises de cor e pH mostraram que as formulações finais apresentaram boa estabilidade físico-química quando armazenadas por 14 dias a diferentes temperaturas. Finalmente, em relação aos estudos dos coeficientes de partição das principais antronas e cromonas presentes nos extratos, obtiveram-se resultados muito promissores utilizando misturas binárias ou ternárias do sistema bifásico água + butan-1-ol + acetato de etilo, em função dos compostos alvo.
39
Chen, pei-ting, i 陳姵廷. "The antioxidative properties of solvent extracts from mushrooms". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/73793322639592355523.
Streszczenie:
碩士中國文化大學
生活應用科學系
100
The study is designed to explore the antioxidant properties of mushroom extracts and the effects of extraction solvents; in addition, to investigate the contents and profiles of total phenolics, including both soluble free and bound forms, by applying solvent extraction, alkaline hydrolysis, and liquid-liquid extraction methods. Five mushrooms (Hypsizygus marmoreu, Flammulina velutipes collybia velutipes , Pleurotus eryngii, Pleurotus citrinopileatus, Lentinus edodes) were investigated and five antioxidant capacities (DPPH scavenging activity, reducing power, ferrous chelating effect, superoxide anion scavenging activity and trolox equivalent antioxidant capacity (TEAC)) were measured. The results showed significant differences (p < 0.05) in the chemical compositions of the samples. Among five antioxidant capacities, mushroom extracts possessed only DPPH scavenging activity, reducing power, and TEAC, which activities were related to the varieties of mushroom. To these three antioxidant activities, Pleurotus citrinopileatus and Pleurotus eryngii were the highest. Pleurotus citrinopileatus had the highest total phenolic content (7.36 mg gallic acid equiv/g), followed by Pleurotus eryngii, Lentinus edodes, Hypsizygus marmoreu and Flammulina velutipes Collybia velutipes. The major portion of phenolics in mushrooms existed in the free form (51% in Hypsizygus marmoreu, 75% in Flammulina velutipes collybia velutipes, 70% in Pleurotus eryngii, 56% Pleurotus citrinopileatus, 69% in Lentinus edodes). The higher content of total phenolics and antioxidant activity were obtained from extraction with 80% acetone with comparision to 100% methanol. Key words: mushrooms, antioxidant, phenolics
40
Taqui, Syed Usman. "Fractionation of hydro-ethanolic extracts from grape pomace through membrane processing: the effect of membrane and extracting media on process performance". Master's thesis, 2014. http://hdl.handle.net/10362/13289.
Streszczenie:
The EM3E Master is an Education Programme supported by the European Commission, the
European Membrane Society (EMS), the European Membrane House (EMH), and a large
international network of industrial companies, research centers and universitiesGrape pomace are generated as waste in juice and winemaking industry in huge quantities. Studies have shown that nutrient extracts from these particular plant matrices garner myriad of benefits in health and nutraceuticals sector. Moreover, the newer recognition of monomeric and oligomeric phenolic compounds as bioactive molecules of commercial value such as gallic acid, catechin, epicatechin, quercetin and resveratrol gives scope for its extensive study and extraction from the pomace. The need for optimizing the biocompatible solvent extraction of ethanolic-water composition is realized and the kinetics of extraction time is demonstrated. The work focusses on novel use of membrane technology for separation and fractionation of lower flavan-3-ols from the crude extract. Four different membranes of varied pore size, chemical nature and material were chosen. Of these, Duramem 900, a class of Organic Solvent Nanofiltration membrane showed lower rejections of monomeric and oligomeric phenolic compounds. This membrane was then subjected to the comparative study of nanofiltration and diananofiltration.
European Commission
41
Mei, Wu Shu, i 吳淑媄. "Study of the release of Polygonum Cuspidatum extract adsorbed on different fibrous membranes in solvents". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/06223910322346785564.
Streszczenie:
碩士中華科技大學
健康科技研究所
103
Several polyphenols found in Polygonum Cuspidatum possess anti-whitening, anti-oxidant, anit-inflammatory, antibiotic and anti-tumor properties. In addition, the extract from olive leaf containing oleuropein, a polyphenol with secoiridoid structure, might serve as a natural surfactant. This study tried to examine the release of bioactive polyphenols from Polygonum cuspidatum extract (PCE) adsorbed on different fibrous membranes in various solvents. The materials of fibrous membranes included electrospun silk fibroin (SF)/chitosan (CS) composite fibrous membrane (SFCS), polyacrylnitrile fibrous membrane (PAN) and commercially available silk fibroin membrane (SFM). We also investigated the effects of co-adsorption of natural surfactant OLE with PCE or addition of OLE in release buffer on the release of the bioactive ingredients in PCE. The results showed that: (1) among the various composition of PCE/SFCS, SFCS8 exhibited the optimum result of controlled release; (2) the release of non-polar emodin could be induced by the addition of OLE in the buffer; (3) co-adsorption of natural surfactant OLE with PCE or addition of OLE in the buffer would exerted beneficial effect on the release of polydatin in PCE. These results could provide ideas for the application of encapsulated polyphenols in nano-fibrous membranes in natural products research.
42
Tseng, Guo-Hsiang, i 曾國香. "Antioxidant and liver cell protective activities of solvent extracts from banana bracts and male flowers". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/25614112258645780416.
Streszczenie:
碩士國立屏東科技大學
食品科學系所
103
Banana Musa spp. (AAA), a member of perennial herb, is the fruit of banana trees. It is one of the most common fruit all over the world due to its high production. According to the literature that the banana has a rich dietary fiber, potassium, magnesium and many other substances beneficial to humans. The banana also increases capacities of immunity, anti-oxidation and anti-cancer, improves cardiovascular health, lowers blood pressure and even affects the treatment of depression. Banana farmers remove the banana flower after banana tree bears fruits in order to control the qualities and nutrition of the banana fruits. Banana flower can be cooked as dishes or made into many other food production; however, tons of banana flower is treated as agricultural waste and dumped in Taiwan every year. In previous studies, banana fruits have showed the capacities of anti-inflammatory and hepatoprotective, but studies related to banana flowers, especially banana buds and bracts, are less than fruits. Therefore, this study was going to analyze total phenol, total anthocyanins, total flavonoids and antioxidant capacity of three solvents extract of banana buds and bracts, which are treated as agricultural wastes while the banana fruits are harvested. Moreover, this study analyzed banana buds and bracts protective ability on injured FL83B liver cells. The results showed that the methanol extraction of banana buds has the maximum contents of total phenol and total flavonoids while the ethanol extraction of banana bracts has the maximum contents of total anthocyanins. Moreover, the methanol extraction of banana buds also has the better antioxidant capacity via DPPH radical scavenging, TEAC and other antioxidant capacity analysis. Toxicity test of mice normal liver cells (FL83B) found that the samples can contribute a better cell growth. And in protection test of the alcohol-induced liver injury, 400μg/mL concentration of methanol extraction of banana buds has significant protection to the mice normal liver cells and their survival rate is up to 92.74%. Besides, 800μg/mL concentration of water extraction of banana buds, methanol extraction of banana bracts and water extraction of banana bracts have obvious results, their rates are up to 89.39%, 91.17% and 85.75% respectively. In conclusion, the banana agricultural waste, such as banana buds and bracts, has considerable potential to be developed as a wonderful antioxidant or a health care food to prevent alcohol injury. Moreover, the new usage of the waste can increase the economic value of agricultural products and also reduce waste.
43
Chen, Xan-Hui, i 陳心慧. "Effects of the organic solvent extracts of the fermented mycelia extracts of Antrodia Camphorata on the hepatic antioxidation and drug-metabolism systems of rats". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/68045007401106252591.
Streszczenie:
碩士中山醫學大學
營養科學研究所
92
Antrodia Camphorata（Niu-chang-chih）is a local fungi specie found in Taiwan. It seems to only grow on elder Niu-chang tree（Cinnamomum Kanehirai Hay）. Based on various reports, Antrodia Camphorata has been regarded as a function food. In previous studies, the mycelium, fruit body, mycelium fermentative extracts of Antrodia Camphorata（MFEAC）have been used as experimental materials to investigate whether Antrodia Camphorata owns health-improved physiological activities. Among those Antrodia Camphorata products, MFEAC and its possible active components is much less studied as compared with the mycelium and fruit body. In this study, solvents with various polarity including water, ethanol, ethyl acetate and ether were used to extract the MFEAC. Following vacuum-condensation and freeze-dry of these solvent extracts, male Sprrague-Dawley rats were orally administered 25 or 100 mg/kg water and ethanol extracts or 5 or 25 mg/kg ethyl acetate and ether extract four times a week for seven weeks. The control rats received ddH2O only. At the end of experimentation, the final body weight and the relative weight of liver, kidney and spleen are not affected by the administration of those four different solvent extracts of MEFAC in either low or high dose. GSH and total GSH levels, however, were significantly lower in rats treated with 25 or 100 mg/kg ether extracts, or in rats dosed with 5 mg/kg ethyl acetate or ether extracts as compared to the control（p＜0.05）. Regarding to the antioxidant system, hepatic glutathione（GSH）peroxidase and GSH reductase activities were similar between each treated and control groups, but hepatic SOD activity was significantly higher in rats treated with 25 or 100 mg/kg water or ethanol extracts or 25 mg/kg ethyl acetate（p＜0.05）as compared to control rats. The endogenous TBARS level or TBH- or FeSO4- induced TBARS production were not changed by either solvent extracts. Hepatic ethoxyresorufin O-deethylase, pentoxyresorufin O-depentylase, N-nitrodimethylamine demethylase and erythromycin demethylase activities and also the expression level of cytochrome P450（CYP）2B1, 2E1and 3A1 were not changed by those solvent extract of MFEAC. In contrast, regardless of the solvents used, CYP 1A1 level was noted to increase in rats treated with either one of the MFEAC extracts as compared to the control rats. Moreover, protein level of the π form of GSH S-transferase was also higher in the MFEAC extract treated rats than the controls. Thease results suggested that the solvent extract of MFEAC may increase hepatic SOD activity but decrease GSH content, and may not change the lipid peroxidation in livers. Moreover, the solvent extracts of MFEAC increase the expression of CYP 1A1 and PGST, it shows MFEAC contains biologically active components that can alive in various organic solvent extracts of MFEAC.
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LIU, SHANG-YUNG, i 劉上詠. "Antioxidant activities and inhibitory activities of hyperglycemic related factors for solvent extracts from Phyllanthus emblica L". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/q7x4z3.
Streszczenie:
碩士東海大學
食品科學系
107
Phyllanthus emblica L. which belongs to the Euphorbiaceae plant widely distributs in tropical and sub-tropical area and has been applied traditional medical systems in China and India for long time. In this study, the fruits of Phyllanthus emblica L. grown in Taiwan were extracted with six different solvents (95% methanol, 95% ethanol, 50% methanol, 50% ethanol, boiling water and ethyl acetate) and examined the functional ingredients, antioxidant activities and hyperglycemic related factors inhibitory activities. Among them, both 50% methanol and 50% ethanol extracts had the highest total phenolic, total flavonoids and hydrolyzed tannin content; The 50% methanol extract showed the highest free radical scavenging activity of DPPH and ABTS with IC50 of 7.51 ± 0.08 and 3.43 ± 0.11 μg/mL, respectively. The ethyl acetate extract had highest superoxide anion radical scavenging activity with IC50 48.27 ± 0.02 μg/mL. The lipid peroxidation were not significantly different regardless of methanol and ethanol concentration. The 50% methanol extract also had highest inhibitory activity of alpha-glucosidase with IC50 0.24 ± 0.02 μg/mL. All extracts had the same AGEs formation inhibitory activity up to 60% inhibition rate. The content of special functional compounds in all extract varied with different solvents. β-Glucogallin had the highest content in each extracts. In conclusion, both 50% methanol and 50% ethanol extracts had the best antioxidant and hyperglycemic related factors inhibitory activity.
45
Papoutsis, Konstantinos. "Optimized conditions for the preparation of citrus by-product aqueous extracts enriched in polyphenols and antioxidants". Thesis, 2018. http://hdl.handle.net/1959.13/1398745.
Streszczenie:
Research Doctorate - Doctor of Philosophy (PhD)A large amount of lemon (Citrus limon L.) by-product is annually generated by the juice industry and is usually disposed to the land, constituting a severe environmental problem. Several studies have shown that citrus waste could be a good source of polyphenols which are compounds with antioxidant, antimicrobial, and antifungal properties. To date, the recovery of polyphenols from citrus by-products is performed by the use of organic solvents or their mixture with water. However, some disadvantages of the organic solvent use should be taken into consideration, including toxicity of organic solvent for human health and environment, solvent purchase and disposal costs, special storage requirements, and solvent residues in the final product. Pure water should be considered as an alternative solution, however, it leads to significantly lower recovery yields. The solution in this matter could be the application of appropriate drying conditions for high retention of polyphenols in the material before extraction, as well as the optimisation and selection of the extraction conditions employed for the recovery of polyphenols. After extraction polyphenols are prone to oxidation, and encapsulation should be employed for the protection of the extracted compounds. The encapsulation conditions, should be carefully selected, since inappropriate conditions could lead to a significant loss of polyphenols and antioxidants. According to the literature (Chapter 1) only a few studies have been conducted investigating the effect of different spray-drying conditions for the encapsulation of citrus extracts, using mainly whey protein isolate as a coating agent. Thus the current research was designed to address the following aspects: (i) investigating the effect of pre-treatment of the material before extraction on the retention of polyphenols and antioxidants, (ii) determining the optimum extraction conditions for polyphenols and antioxidants from lemon by-products, (iii) assessing the antifungal activities of the aqueous extracts against phytopathogenic fungi, and (iv) investigating the effect of different encapsulation conditions on the entrapment of polyphenols and antioxidants. The effect of three different drying techniques (freeze-drying, vacuum-drying, and hot air-drying) was investigated and the results showed that drying method significantly affects the physicochemical properties of the dried material, with hot air- and vacuum-drying techniques resulting in higher retention of polyphenols and antioxidants in the dried material compared to the freeze-drying. However, freeze-drying resulted in a dried product with significantly lower moisture content and water activity. In contrast to the freeze-drying, drying at high temperatures either by hot air- or vacuum-drying led to colour changes (browning) (Chapter 2). Two extraction techniques (hot water extraction (HWE) and aqueous ultrasound-assisted extraction (AUAE)) were optimised and compared with an organic solvent conventional extraction (OSCE) technique (Chapter 3). The results revealed that the optimum HWE resulted in extracts with the highest polyphenol content and antioxidant capacity compared to AUAE and OSCE in a considerably shorter time. These results were further supported by the application of scanning electron microscopy. Extracts obtained at the optimum HWE conditions showed high in vitro antifungal activities against Alternaria alternata, a fungus that causes losses in fruits and vegetables. The antifungal activity of the extracts was attributed to the presence of phenolic acids and ascorbic acid into the aqueous extracts. Lemon by-product extracts significantly changed the morphology of fungus hyphae, leading to a cell wall collapse and loss of linearity (Chapter 4). Two encapsulation techniques (spray-drying and freeze-drying) were investigated and compared using different coating agents (Chapter 5). Freeze-drying and a mixture of maltodextrin with soybean protein isolate were found to be the most efficient for the highest retention of polyphenols and antioxidants. Moreover, the encapsulated powder obtained by freeze-drying had significantly lower moisture content and water activity (aw) than that obtained by spray-drying. Scanning electron microscopy revealed that spray-drying resulted in the formation of spherical particles of different sizes with concavities, regardless the type of the wall material being used. Although freeze-drying resulted in powders of amorphous glassy shapes, the mixture of maltodextrin with soybean protein isolate as wall material resulted in the formation of spherical porous materials. In conclusion, in this study lemon by-products have been converted to value-added products which have the potential of being utilised by both pharmaceutical and food industries. The results presented in this thesis showed that apart from the selection of extraction conditions, sample pre-treatment (i.e. sample drying) is a crucial step and should be considered for the preparation of products from citrus wastes with high antioxidant and antifungal properties.
46
Ludere, Tshimangadzo Margaret. "The effect of diabietic acid on the coking of oxidised solvent - extracted coal". 2006. http://upetd.up.ac.za/thesis/available/etd-04172008-140302.
47
Ludere, Margaret Tshimangadzo. "The effect of diabietic acid on the coking of oxidised solvent-extracted coal". Diss., 2007. http://hdl.handle.net/2263/23996.
Streszczenie:
Refcoal is a refined carbon source obtained by extraction of coal with dimethylformamide (DMF). During the coking process, Refcoal goes through a mesophase (fluid) stage to form an anisotropic coke. In contrast, oxidised Refcoal does not undergo such a mesophase stage during the carbonisation process. Thus it does not yield an anisotropic coke, but forms an isotropic coke. The objective of this study is to produce an anisotropic coke from oxidised Refcoal. For this purpose, diabietic acid, a hydrogen donor, was considered as a suitable additive. Coking was performed in sealed glass capillary tubes as diabietic acid proved to be volatile at the carbonisation temperature of 500 °C. The resultant cokes were analysed using thermogravimetric analysis, Raman spectroscopy and optical microscopy. The results show that the degree of anisotropy increased with diabietic acid content (3, 5 and 10 mass %).Dissertation (MSc (Chemistry))--University of Pretoria, 2008.
Chemistry
MSc
Unrestricted
48
Sobral, Ana Isabel Baltazar. "Efeito do solvente nas propriedades antioxidantes e no conteúdo em compostos fenólicos de extratos de frutos e folhas de Rubus". Master's thesis, 2012. http://hdl.handle.net/10400.1/3124.
Streszczenie:
Dissertação de mest., Engenharia Biológica, Faculdade de Ciências e Tecnologia, Univ. do Algarve, 2012O presente estudo teve como principal objetivo avaliar o efeito do solvente na atividade antioxidante e no conteúdo em compostos fenólicos de extratos aquosos, etanólicos e metanólicos obtidos a partir de frutos e folhas de plantas de Rubus cultivadas e não cultivadas (coletadas no campo) obtidas no sul do País. Nos extratos obtidos de frutos estudados, o espécime RUN2 apresentou os conteúdos em compostos fenólicos (2,57 mg GAE/g amostra fresca) mais elevados (fenólicos totais, flavonoides totais, antocianinas monoméricas totais e taninos condensados) e a maior atividade antioxidante (4,16 mg TE/g amostra fresca). Os extratos aquosos a 95 C e os metanólicos foram o que apresentaram a maior capacidade em extrair estes compostos. Da análise dos resultados dos extratos de folhas de plantas de Rubus ressalta que o espécime não cultivado do Algarve (RUN2) apresenta o maior conteúdo em compostos bioativos e a maior atividade antioxidante. Quanto aos diferentes solventes usados nas extrações das folhas, o extrato C) mostrou o maior poder de extração de compostos bioativos (15,09 mg GAE/g amostra seca) e de antioxidantes (34,80 mg TE/g amostra seca). Na avaliação da atividade antioxidante destes extratos foram realizados vários ensaios. O método ABTS foi, efetivamente, o que apresentou os melhores resultados, indicando que os compostos possuem elevada capacidade para reduzir o radical ABTS●+. O método DPPH mostrou as concentrações mais baixas, sugerindo que os antioxidantes presentes nestes extratos não possuem capacidade para reduzir o radical livre DPPH como possuem para reduzir o radical ABTS●+ e/ou ferro (III). Quanto à avaliação dos perfis de compostos fenólicos individuais (HPLC-DAD) presentes nos extratos, as antocianinas e os ácidos hidroxibenzóicos foram os que apresentaram os teores mais elevados. Assim, a forte correlação existente entre o conteúdo em compostos fenólicos e a atividade antioxidante encontrada nestes frutos (R2=0,949) e folhas (R2=0,857) pode ser explicada pela presença destes compostos maioritários, sugerindo que os fenólicos são os principais responsáveis pela atividade antioxidante existente nestes extratos. Conclui-se, então, que as folhas e frutos das plantas estudadas constituem fontes ricas em compostos biologicamente ativos, que possuem importantes propriedades antioxidantes, podendo contribuir significativamente para as exigências das dietas nutricionais e devendo ser fontes de nutrientes complementares a outras fontes principais.
49
Chen, Wei-Di, i 陳蔚迪. "Cytotoxicities induced by the water-soluble species and organic-solvent extract of atmospheric coarse and fine particles". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/05661875665751668919.
Streszczenie:
碩士國立屏東科技大學
環境工程與科學系所
95
Atmospheric coarse (PM2.5-10) and fine (PM2.5) particles, collected from September 2005 to May 2006 at TEPA’s Pingtung (three-story high) and Chaochou (one-story high) air quality monitoring stations, were extracted by ultra-pure water and an organic solvent, respectively. The organic solvent extracts were then treated by Dimethyl Sulfoxide (DMSO) substitution. The water-soluble extracts and the substitution fluids were tested for cellular cytotoxicities, denoted as the cumene-hydroperoxide equivalent concentration (CEC). All cytotoxicity assays were carried out on MRC-5 cell (male lung epithelial cells) lines and assessed using a 3-(4,5-dimethylthiazol-2-yl)-5-(3- carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetra-zolium(MTS) cytotoxict- y assay to explore the toxicity responses indcuced by the two types of particle extracts to MRC-5. The results show that the CEC values of water-soluble extracts for the PM2.5 and PM2.5-10 at Pingtung station (N=40) were 0.04-337 (mean = 66.3 ± 88.7) and 0.01-76.1 (mean = 14.2 ± 19.4) μM as CHP/m3 air, respectively, while those at Chaochou station (N=40) were 2.46-273 (mean = 54.5 ± 65.9) and 0.02-18.6 (mean = 4.13 ± 4.41) μM as CHP/m3 air, respectively. At the Pingtung station, the CEC values of organic-solvent extracts for the PM2.5 and PM2.5-10 were 1.21-1811 (mean = 283 ± 402) and 0.08-1898 (mean = 193 ± 351) μM as CHP/m3 air, respectively, whereas the values were 16.2-742 (mean = 277 ± 229) and 2.63-608 (mean = 158 ± 147) μM as CHP/m3 air, respectively, at the Chaochou station. The average CEC cytotoxicities of water-soluble and organic-solvent extracts to MRC-5 were higher for PM2.5 than for PM2.5-10 at both the stations. The exponential regression models obtained from this study to relate CEC with the concentrations of PM2.5- and PM2.5-10-bearing water-soluble extracts at Pingtung station are CEC = 0.1122e0.092PM2.5-10 (R2=0.391) and CEC = 0.595e0.0494PM2.5 (R2=0.427), respectively, while they are CEC = 0.4039e0.0577PM2.5-10 (R2=0.182) and CEC = 2.447e0.0322PM2.5 (R2=0.574), respectively, at Chaochou station. The similar models relating CEC with the concentrations of PM2.5- and PM2.5-10-bearing organic-solvent extracts at Pingtung station show CEC = 11.14e0.049PM2.5-10 (R2 = 0.2190) and CEC = 6.751e0.0388PM2.5 (R2= 0.351), respectively, while at Chaochou station CEC = 25.94e0.0593PM2.5-10 (R2=0.242) and CEC = 35.5e0.0226PM2.5 (R2=0.387) , respectively. At both stations, it demonstrated that the higher the fine and coarse particle concentrations, the stronger the water-soluble extracts and organic-solvent extracts induced cytotoxicity, especially for the fine particles. The average CEC cytotoxicities to MRC-5 of organic-solvent extracts were significantly higher than those of water-soluble extracts for both PM2.5 and PM2.5-10 at the two stations.
50
Vieira, Pedro Gonçalo Simões. "Produção de extratos bioativos a partir de resíduos de Quercus cerris por extração supercrítica com solventes verdes". Master's thesis, 2018. http://hdl.handle.net/10773/24408.
Streszczenie:
Esta dissertação teve como objetivo estudar a produção e caracterização de extratos ricos em compostos bioativos (nomeadamente fridelina) a partir de cortiça de Quercus cerris. Realizaram-se extrações Soxhlet e extrações sólido-líquido (SLE) em descontínuo com metanol, etanol, diclorometano e éter de petróleo, assim como extração supercrítica (SFE) com dióxido de carbono modificado (por adição de etanol). Os extratos produzidos foram caracterizados por FTIR-ATR e GC-MS e o método de escalonamento multidimensional (MDS) foi aplicado para comparação dos mesmos. Realizou-se uma otimização experimental de SFE, usando um desenho fatorial de experiências do tipo Box-Behnken e a metodologia de superfícies de resposta.
O rendimento total de extração (𝜂Total) máximo foi obtido para o ensaio Soxhlet com metanol (𝜂Total = 13.8 wt.%) e o rendimento mínimo foi obtido para extração sólido-líquido em descontínuo com éter de petróleo (𝜂Total = 0.35 wt.%). Registou-se uma variabilidade significativa dos valores de 𝜂Total, marcada pelos rendimentos superiores para extração com solventes polares, nomeadamente metanol e etanol. No caso da extração supercrítica, 𝜂Total variou de 1.2 wt.% no ensaio SFE3 (50 ℃, 2.5 wt.% EtOH, 5 g min−1) até 1.7 wt.% no ensaio SFE4 (60 ℃, 2.5 wt.% EtOH, 8 g min−1). Em termos de concentração em fridelina (𝐶Friedelin), os resultados oscilaram entre 41.3 wt. % (Soxhlet com diclorometano) e 5.4 wt. % (SLE em descontínuo com éter de petróleo). Os melhores resultados em termos de 𝐶Friedelin foram os que envolveram solventes pouco polares/apolares. Os ensaios SFE atingiram resultados de 𝐶Friedelin melhores do que a maioria dos ensaios de extração Soxhlet e sólido-líquido em descontínuo, o que confirma a interessante seletividade do processo para a fridelina. A análise MDS destacou a maior proximidade química entre os extratos alcoólicos e a biomassa, e entre os extratos de solventes apolares ou pouco polares e a fridelina pura.
Para a otimização experimental de SFE da cortiça Q. cerris, as condições que maximizam 𝜂Total (2.2 wt.%) e 𝛼F,nF (3.3 para t = 8.0 h) são valores máximos de 𝑇 (60 ℃), teor de etanol (5 wt.%) e de caudal de CO2 (11 g min−1). De registar os valores de seletividade superior a 1.0 no espaço experimental estudado, o que confirma que a fridelina é removida seletivamente por SFE. No caso de 𝐶Friedelin, o valor máximo (38.2 wt.%) foi obtido para a combinação de baixa temperatura (40 ℃), ausência de cossolvente (0 wt.% EtOH) e menor caudal (5 g min−1). Em definitivo, as condições ótimas dependerão de qual o principal objetivo da extração: um extrato rico numa maior diversidade de compostos (maior 𝜂Total) ou em compostos alvo como a fridelina (maior 𝐶Friedelin).
No geral, este trabalho fornece argumentos importantes para a produção de extratos ricos em fridelina a partir da cortiça de Quercus cerris, através da tecnologia SFE no âmbito do conceito de biorrefinariaThe present work studied the production and characterization of extracts rich in bioactive compounds (namely friedelin) from Quercus cerris cork. Soxhlet and batch solid-liquid extraction (SLE) with methanol, ethanol, dichloromethane and petroleum ether were carried out, as well as supercritical fluid extraction (SFE) using modified carbon dioxide (by addition of ethanol). The produced extracts were characterized by FTIR-ATR and GC-MS, and multidimensional scaling (MDS) was applied to compare them. The optimization of SFE was performed using Box-Behnken design of experiments and response surface methodology. The maximum total extraction yield (𝜂Total) was attained for the Soxhlet extraction with methanol (𝜂Total = 13.8 wt.%) and the minimum was attained in batch SLE with petroleum ether (𝜂Total = 0.35 wt.%). A significant variability of 𝜂Total values was evident, marked by the higher yields obtained with polar solvents, namely methanol and ethanol. For the supercritical fluid extractions, 𝜂Total ranged from 1.2 wt.% for run SFE3 (50 ℃, 2.5 wt.% EtOH, 5 g min−1) to 1.7 wt.% for run SFE4 (60 ℃, 2.5 wt.% EtOH, 8 g min−1). For friedelin concentration (𝐶Friedelin), the results ranged from 41.3 wt.% (Soxhlet with dichloromethane) to 5.4 wt.% (batch SLE with methanol). The best performing assays on 𝐶Friedelin were those involving weakly polar/non-polar solvents. The SFE assays provided 𝐶Friedelin results better than most Soxhlet and batch SLE experiments, which confirms the interesting selectivity to friedelin (𝛼F,nF). MDS analysis highlighted the chemical proximity between the alcoholic extracts and the biomass, and between the weakly or non-polar solvent extracts and pure friedelin. For the experimental optimization of SFE of Q. cerris cork, the conditions that maximize 𝜂Total (2.2 wt.%) and 𝛼F,nF (3.3 at t = 8.0 h) were the maximum values of 𝑇 (60 ℃), ethanol content (5 wt.%) and CO2 flow rate (11 g min−1). In fact, the selectivity values were higher than 1.0 anywhere within the studied experimental space, which shows that friedelin can be removed selectively over all the other compounds by SFE. For friedelin concentration, the maximum (𝐶Friedelin= 38.2 wt.%) was attained for the combination of a lower temperature (40 ℃), no cosolvent (0 wt.% EtOH) and lower CO2 flow rate (5 g min−1). The optimal conditions depend on what is the main goal of extraction: an extract enriched in a higher diversity of compounds (higher 𝜂Total) or in a target compound like friedelin (higher 𝐶Friedelin). On the whole, this work provides strong arguments towards the production of friedelin enriched extracts from Quercus cerris cork through SFE technology, under the biorefinery concept
Mestrado em Engenharia Química