Academic literature on the topic 'Ciocalteu'
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Journal articles on the topic "Ciocalteu"
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Komorowski, James, Devon Bernsley, Sarah Sylla, and Sara Perez Ojalvo. "Enhanced Antioxidant Activity of Phycocyanin Oligopeptides." Current Developments in Nutrition 5, Supplement_2 (June 2021): 336. http://dx.doi.org/10.1093/cdn/nzab037_046.
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Abstract Objectives Phycocyanin, a phytonutrient found in blue-green algae, has various beneficial properties, including potent antioxidant effects. The goal of this study was to investigate the antioxidant potency of a novel phycocyanin oligopeptide (PC-O) compared to phycocyanin (PC). Methods Antioxidant potency of PC-O and PC was measured using two different methods: 1) the Folin-Ciocalteu reaction assay, and 2) the Oxygen Radical Absorbance Capacity (ORAC) 6.0 assay. The Folin-Ciocalteu reaction assay (or total phenolics assay) was run using Folin-Ciocalteu's phenol reagent and sodium carbonate. Optical absorbance was measured at 765nm in a colorimetric plate reader with gallic acid as a reference standard. The ORAC 6.0 assay was run to evaluate the antioxidant capacity of a material against six primary reactive oxygen species: peroxyl radical, hydroxyl radical, superoxide anion, singlet oxygen, peroxynitrite, and hypochlorite. Trolox was used as the reference standard, and the results were expressed as μmole Trolox equivalency per gram of a tested material. Results In both assays, PC-O had higher antioxidant potency than PC. In the Folin-Ciocalteu reaction assay, the cellular antioxidant capacity of PC-O (24 mg/L) was greater than PC (16 mg/L). PC-O also demonstrated consistently higher antioxidant activity in the ORAC 6.0 assay, as follows: peroxyl radicals, PC-O (477 μmole TE/gram) vs. PC (26 μmole TE/gram); hydroxyl radicals, PC-O (734 μmole TE/gram) vs. PC (62 μmole TE/gram); peroxynitrite, PC-O (40 μmole TE/gram) vs. PC (7 μmole TE/gram); super oxide anion, PC-O (172 μmole TE/gram) vs. PC (53 μmole TE/gram); singlet oxygen, PC-O (92 μmole TE/gram) vs. PC (70 μmole TE/gram); and hypochlorite, PC-O (2,805 μmole TE/gram) vs. PC (312 μmole TE/gram). Conclusions These results demonstrate that phycocyanin oligopeptide (PC-O) is a superior antioxidant compared to phycocyanin (PC) as shown by its higher cellular antioxidant capacity in the Folin-Ciocalteu reaction assay and significantly higher ORAC 6.0 scores. Funding Sources This work was supported by Nutrition 21, LLC.
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Medina Vargas, Óscar Julio, Luis Carlos Arturo Garzón Salcedo, and Wilfred Edilberto Espinosa Manrique. "Efecto del tiempo sobre la cuantificación de polifenoles totales con el reactivo de Folin-Ciocalteu." I3+ 3, no. 2 (October 2, 2017): 10. http://dx.doi.org/10.24267/23462329.216.
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En este manuscrito se presentan los resultados experimentales obtenidos durante el proceso de cuantificación de polifenoles totales en función del tiempo, mediante la metodología de Folin-Ciocalteu y ácido gálico como molécula de referencia. El trabajo se realizó para obtener el tiempo apropiado de reacción entre el ácido gálicoy el reactivo de Folin-Ciocalteu, dado que en la literatura se encuentra, para esta metodología, un conjunto variado de condiciones que pueden afectar la confiabilidad de los resultados experimentales. Se construyeron 5 curvas de calibración para que el ácido gálico interactuara con el reactivo de Folin-Ciocalteu entre 1,0 y 3,0 horas a intervalos de 30 minutos, y se contrastaron sus valores de pendiente e intercepto entre sí y con los valores de absorbancia del blanco. Se aplicaron las pruebas estadísticas de análisis de varianza de un factor y contraste t para dos medias experimentales. Este estudio permitió demostrar que el tiempo es una variable influyente en la cuantificación de polifenoles totales con el reactivo de Folin-Ciocalteu, y dentro de las condiciones experimentales analizadas se encontró que el tiempo adecuado de interacción fue de 1,0 hora. Palabras clave: ácido gálico, polifenoles totales, reactivo de Folin- Ciocalteu.
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Hong, Jung-Il, Hyun-Jung Kim, and Ji-Yun Kim. "Factors Affecting Reactivity of Various Phenolic Compounds with the Folin-Ciocalteu Reagent." Journal of the Korean Society of Food Science and Nutrition 40, no. 2 (February 28, 2011): 205–13. http://dx.doi.org/10.3746/jkfn.2011.40.2.205.
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Hapsari, Annisa Mulia, Masfria Masfria, and Aminah Dalimunthe. "Pengujian Kandungan Total Fenol Ekstrak Etanol Tempuyung (Shoncus arvensis L.)." Talenta Conference Series: Tropical Medicine (TM) 1, no. 1 (October 2, 2018): 284–90. http://dx.doi.org/10.32734/tm.v1i1.75.
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Daun tempuyung merupakan salah satu tumbuhan obat tradisional Indonesia yang banyak dimanfaatkan untuk pengobatan batu ginjal, anti inflamasi, disentri, radang dan rematik. Tempuyung banyak mengandung senyawa flavonoid yang merupakan golongan fenol terbesar. Penelitian ini dimulai dengan pengumpulan dan persiapan sampel, skrining fitokimia, pembuatan ekstrak etanol, dan pengujian kandungan total fenol dengan metode kolorimetri pereaksi Folin-Ciocalteu menggunakan spektrofotometer UV-Vis dengan asam galat sebagai baku pembanding. Hasil skrining fitokimia menunjukkan daun tempuyung mengandung senyawa flavonoid. Penetapan kadar total fenol menggunakan metode spektrofotometri pereaksi Folin- Ciocalteu didapat nilai regresi y = 0,00077 x + 0,03667 dengan nilai r2 = 0,99757 sehingga didapat nilai rata – rata kadar total fenol 45,04 ± 0,46 mg GAE/g ekstrak.
Tempuyung is one of traditional medical plant in Indonesia and used in kidney stone medication, anti-inflammatory, dysentery, inflammation, and rheumatism. Tempuyung contains substantial flavonoid which considers as the biggest phenol. This research started from the preparation and sample collection, phytochemical screening, ethanol extract preparation, and total phenol test using colorimetry method usingFolin-Ciocalteu reagent byUV-Vis spectrophotometer and gallic acid as the standard compound. The phytochemical screening indicated that tempuyung leaves contained flavonoid compound. The total phenol contentwas determined using colorimetry method of Folin-Ciocalteu reagent and resulted with regression value of y=0.00077 x+0.03667 and the value of r2=0.99757 and the average of total phenolcontent of 45.04 ± 0.46 mg GAE/g.
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Way, Madeleine L., Joanna E. Jones, David S. Nichols, Robert G. Dambergs, and Nigel D. Swarts. "A Comparison of Laboratory Analysis Methods for Total Phenolic Content of Cider." Beverages 6, no. 3 (September 7, 2020): 55. http://dx.doi.org/10.3390/beverages6030055.
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Total phenolic content is widely accepted as a key measure of quality for cider. Apple juice and cider, made from six apple varieties including dessert and cider apples, were analysed for total phenolics using three different methods: (a) the Folin-Ciocalteu method, (b) the Somers method (a spectrophotometric method developed specifically for wine), and (c) ultra-performance liquid chromatography (UPLC) as a benchmark test. Of these approaches, the Somers method had the strongest correlation with UPLC with an R2 value of 0.99, whilst the Folin-Ciocalteu correlated with UPLC with an R2 value of 0.89. The Folin-Ciocalteu method also had a strong positive correlation with the Somers approach with an R2 value of 0.91. Correlations between methods were strongest for apple varieties that were naturally high in phenolic content. These results highlight the potential of the Somers method to rapidly, inexpensively, and accurately report the total phenolic content of apple juice and ciders made from dessert and cider apple varieties.
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Park, Kyung A., Yoo-mi Choi, Smee Kang, Mi-Ri Kim, and Jungil Hong. "Effects of Proteins on the Reactivity of Various Phenolic Compounds with the Folin-Ciocalteu Reagent." Korean Journal of Food Science and Technology 47, no. 3 (June 30, 2015): 299–305. http://dx.doi.org/10.9721/kjfst.2015.47.3.299.
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Berker, Kadriye Isil, F. Ayca Ozdemir Olgun, Dilek Ozyurt, Birsen Demirata, and Resat Apak. "Modified Folin–Ciocalteu Antioxidant Capacity Assay for Measuring Lipophilic Antioxidants." Journal of Agricultural and Food Chemistry 61, no. 20 (May 13, 2013): 4783–91. http://dx.doi.org/10.1021/jf400249k.
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Raza, Asad, and Tariq Mahmood Ansari. "Spectrophotometric Determination of Citalopram in Pharmaceuticals Using Folin-Ciocalteu Reagent." Asian Journal of Chemistry 25, no. 16 (2013): 8913–16. http://dx.doi.org/10.14233/ajchem.2013.14907.
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Gil, Dulce Martins de Albuquerque, and Maria Jose Ferreira Rebelo. "Metabisulfite interference in biosensing and Folin-Ciocalteu analysis of polyphenols." Microchimica Acta 167, no. 3-4 (November 10, 2009): 253–58. http://dx.doi.org/10.1007/s00604-009-0249-9.
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Nikolaeva, Tat'yana Nikolayevna, Petr Vladimirovich Lapshin, and Natal'ya Viktorovna Zagoskina. "METHOD FOR DETERMINING THE TOTAL CONTENT OF PHENOLIC COMPOUNDS IN PLANT EXTRACTS WITH FOLIN-DENIS REAGENT AND FOLIN-CHOCALTEU REAGENT: MODIFICATION AND COMPARISON." chemistry of plant raw material, no. 2 (June 10, 2021): 291–99. http://dx.doi.org/10.14258/jcprm.2021028250.
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A modification of the method for determining the total content of phenolic compounds in plant tissue extracts with the Folin-Denis reagent and the Folin-Ciocalteu reagent has been carried out, allowing to establish the correspondence of the results obtained when using them. The method using the Folin-Denis reagent is adapted for conducting determinations in microvolumes. For the method using the Folin-Ciocalteu reagent, the concentration of the latter (0.4 N, a 5-fold dilution of the standard reagent) and the composition of the reaction mixture were selected, using which the optical densities of the reduction products of the Folin-Denis and Folin-Ciocalteu reagents containing polyphenols in ethanol extracts from wheat, buckwheat and calus tissue of tea were almost the same. The absorption spectra of the reduction products of these reagents by gallic acid, rutin, (-)-epicatechin, as well as ethanol extracts from wheat, buckwheat, and tea calus tissue, were located in the same region (680–770 nm) and had similar characteristics. Calibration graphs of the dependence of the optical density of solutions on the concentration of standard substances (gallic acid, (-)-epicatechin, rutin), constructed using the Folin-Denis and Folin-Ciocalteu reagents, had a linear character within the concentration range of 10–100 μg/ml and practically coincided. The results of determining the content of phenolic compounds in ethanol extracts of plants, differing in their ability to accumulate, showed very similar and statistically significant values when using these two reagents.
Dissertations / Theses on the topic "Ciocalteu"
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Torres, Priscila Bezerra. "Análise de pigmentos fotossintetizantes e substâncias fenólicas em Gracilariopsis tenuifrons (C. J. Bird & E. C. Oliveira) Fredericq & Hommersand em diferentes intensidades de luz." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/41/41132/tde-19122012-214148/.
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O estresse de luz pode afetar consideravelmente o crescimento e o desenvolvimento dos organismos fotossintetizantes. Nestas situações, é comum verificar respostas químicas que podem indicar diferentes estratégias de fotoproteção adotado pelo organismo. No presente trabalho, foram desenvolvidas metodologias de análise e extração de pigmentos fotossintetizantes e compostos fenólicos na macroalga vermelha Gracilariopsis tenuifrons com o objetivo de avaliar os efeitos do aumento intensidade de luz sobre estes compostos. Foi verificado que aumento da intensidade de luz não provocou redução na biomassa desta alga, ao contrário houve um maior incremento. Os pigmentos majoritários no extrato foram clorofila α, β-caroteno e zeaxantina. O carotenoide β-caroteno teve um comportamento correlacionado com o pigmento clorofila a, tendo as concentrações reduzidas com o aumento da intensidade de luz, sugerindo que ambos os pigmentos possuam uma mesma função na fotossíntese. Já a concentração da zeaxantina aumentou com a intensidade de luz nos dias iniciais, indicando uma função fotoproteção deste pigmento nesta alga. A capacidade redutora do extrato aumentou com a intensidade luminosa. No entanto, não foi possível afirmar se esse aumento foi realmente devido à síntese de compostos fenólicos ou a outras substâncias que desempenhem o mesmo papel. As análises em CLAE revelaram que um derivado da micosporina palitinol apresentou alta relação com o aumento da intensidade de luz, sendo essa resposta altamente correlacionada com os resultados no ensaio no Folin-Ciocalteu. Em conclusão, das substâncias analisadas neste trabalho, a zeaxantina e o derivado do palitinol foram as que apresentaram os resultados mais evidentes como antioxidantesThe high-light stress can adversely affect growth and development of photosyn-thetic organisms. In these situations, it is common to note chemical responses that may indicate different strategies of photoprotection. In this study, protocols were optimized for analysis and extraction of phenolic compounds and photosynthetic pig-ments in macrophytic red algae Gracilariopsis tenuifrons in order of evaluat-ing the effects of high-light stress on these compounds. It was found that an increase in light intensity has not caused decrease in biomass of algae; on the contrary, promotes a greater increase in biomass. Zeaxanthin, β-carotene and chlorophyll α were the major pigments present in the extract. The β-carotene and chlorophyll a were inversely dependent on the intensity of light. Both pigments were highly correlated sug-gesting the same role in photosynthesis. The concentration of the zeaxanthin was de-pendent on the intensity of light in the initial days, indicating a photoprotection function for this pigment. The reduction capacity of the extract increased with light intensity. However, it was not possible to state that this increase was actually due to the synthesis of phenolic compounds or other substances that perform the same role. The HPLC ana-lyzes revealed that a derivative of micosporina palitinol showed high correlation with the increase in light intensity. This response was highly correlated with the results for Folin-Ciocalteu assay. In conclusion, from all compounds analyzed in this work, zeax-anthin and the palitinol derivative presented clearer results as antioxidants
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Ewing, Brianna Leigh. "Managing Apple Maturity and Storage to Increase the Quality of Virginia Hard Ciders." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/74928.
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Though the cidermaking process is very similar to that of winemaking, there is a lack of scientific knowledge as to how orchard management practices and fruit storage affect the quality of the resulting cider. This research examined how both varying harvest maturities and post-harvest storage temperatures and durations in apple cultivars Dabinett, Brown Snout, and York impacted fruit quality as well as the chemistry of the juice and cider. Harvest intervals of two weeks before maturity, at maturity, and 2 weeks after maturity resulted in significant differences in fruit quality and juice chemistry, but few of these differences persisted in cider chemistry. Nonetheless, differences in concentration of some individual polyphenols determined by UPLC-MS were observed in ciders made from fruit harvested at different stages. For example, cider made from optimally mature Dabinett had over 250% the concentration of procyanidin B5 that was found in cider made from fruit harvested earlier or later. The storage treatments also resulted in substantial differences in fruit and juice chemistry, but fewer differences in cider chemistry. As with the harvest maturity experiment, differences in individual polyphenols were detected, with ciders made from cv. York having 20% higher epicatechin concentration when stored for 6 weeks at 1°C rather than 10°C. Finally, the accuracy of the Folin-Ciocalteu (FC) assay, commonly used for quantification of total polyphenols in fruit juices and fermented fruit beverages was critically evaluated. Reducing sugars in the sample matrix did not affect the results of the FC assay, whereas the presence of the amino acid tyrosine resulted in significant overestimation of total polyphenols in fruit juice by the FC assay.Master of Science in Life Sciences
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Sá, Luísa Zaiden Carvalho Martins de. "Determinação eletroanalítica e espectrofotométrica da atividade antioxidante de fermentados de jabuticaba e vinhos de diferentes procedências." Universidade Federal de Goiás, 2013. http://repositorio.bc.ufg.br/tede/handle/tede/3359.
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The consumption of wine has been associated with health promoting properties due to the high content of phenolic compounds, what makes wines an important dietary source of antioxidants. Jabuticaba fermented beverages, as much as wine, have a high content of phenolic compounds. In this study, traditional spectrophotometric methods (ABTS, DPPH, Folin-Ciocalteu) as well as novel methods (Cyclic Voltammetry - CV, Differential Pulse Voltammetry - DPV and Square Wave Voltammetry - SWV) have been used to evaluate the antioxidant activity of wines of different origin a jabuticaba fermented beverages and a jabuticaba brandy. Furthermore, an Electroanalytical Index (EI) has been proposed in order to allow the comparison of the antioxidant activity measured by electroanalytical methods. For the fermented beverages of jabuticaba, it has been demonstrated in the five methods that all three varieties, red, white and rose, have high antioxidant potential, very similar to a red dry wine, while the brandy has not shown any peaks in voltammetric analysis. In the analyzes by DPPH, red wines have shown about five times as much the antioxidant capacity of white wines, while for the EI it is twice as much when compared to white wines. Rose, white and fortified wines have shown lower EI than the red wine. It has been determined a Pearson correlation of -0.91097 between the DPPH method and the EI. The proposed EI allows comparison of the amount of electroactive compounds determined in the various wine samples analyzed. Considering the electroactive nature of the antioxidant compounds, electroanalytical methods have been demonstrated suitable for studying such compounds. Its main disadvantage was the high adsorption process due to the phenolic oxidation on the electrode´s surface, creating an isolating film on it. This process has been overcome by the use of carbon paste electrode.
O consumo de vinhos tem sido associado a benefícios à saúde por conter alto teor de compostos fenólicos, o que os torna uma importante fonte alimentar de antioxidantes. Bebidas fermentadas de jabuticaba, assim como os vinhos, também apresentam alto teor de compostos fenólicos. No presente trabalho, foram utilizados métodos espectrofotométricos clássicos (ABTS, DPPH, Folin-Ciocalteu) bem como métodos inovadores (voltametria cíclica, voltametria de pulso diferencial e voltametria de onda quadrada) para avaliação da atividade antioxidante de vinhos de diferentes origens e de bebidas fermentadas de jabuticaba e de uma aguardente de jabuticaba. Além disso, foi proposto um índice eletroanalítico (EI) que permite a comparação da atividade antioxidante medida pelos métodos eletroanalíticos. Para os fermentados de jabuticaba, foi demonstrado em todos os cinco métodos que todas as três variedades, a tinta, a rosê e a branca, apresentam potencial antioxidante elevado, bastante semelhante ao de um vinho tinto seco, enquanto a aguardente de jabuticaba não apresentou nenhum pico nas análises voltamétricas. Nas análises por DPPH, os vinhos tintos demonstraram possuir cerca de cinco vezes mais capacidade antioxidante que os vinhos brancos; já para EI, a diferença encontrada foi de cerca de duas vezes. Os vinhos rosê, branco, espumantes e fortificados demonstraram EI inferior ao dos vinhos tintos. Foi determinada uma correlação de Pearson de -0,91097 entre o método de DPPH e o EI. O EI proposto permite a comparação entre a quantidade de compostos eletroativos encontrados nas diferentes amostras de vinhos analisadas. Considerando-se a natureza eletroativa que os compostos antioxidantes apresentam, os métodos eletroanalíticos demonstraram ser métodos adequados, simples e rápidos para o estudo de tais compostos. A principal desvantagem encontrada nas análises por esse método foi a forte adsorção dos compostos fenólicos devido ao processo de oxidação que eles sofrem, formando um filme isolante na superfície do eletrodo, fato este contornado pelo uso de eletrodos de pasta de carbono.
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Bezerra, Aline Sobreira. "CARACTERIZAÇÃO DE COMPOSTOS ANTIOXIDANTES EM GRÃOS DE DIFERENTES CULTIVARES DE CEVADA (Hordeum vulgare L.)." Universidade Federal de Santa Maria, 2009. http://repositorio.ufsm.br/handle/1/5658.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorAntioxidants are compounds known as free radicals react with and/or reactive oxygen species in order to idle them, preventing the oxidative damage. Many studies have pointed to the imbalance between oxidants and antioxidants as the cause of many diseases and because of the great importance given to this issue, there is a strong demand for studies involving the identification and quantification of compounds with antioxidant activity. This work was then identify and quantify the polyphenolic compounds full of grains of Brazilian cultivars of barley, grown in the municipality of Ibiaçá/RS, in the agricultural year of 2005 and 2006, from the Research Center of Embrapa/Wheat, Passo Fundo/RS and assess the weather conditions (average temperature, precipitation index and insolation) between the time of planting and harvesting barley in the quantification of phenolic compounds between the different seasons. The samples were characterized chemically related to the presence of polyphenols, using the method of separation based on the system of high performance liquid chromatography in reversed phase (RP-HPLC) with UV-VIS detection to 254 nm. We identified the phenolic compounds rutin, caffeic acid, ferulic acid, quercitrin and myricetin, with rutin and caffeic acid the most abundant among cultivars. Alongside was a quantification of phenolic compounds by the Folin-Ciocalteau technique of aiming at a comparison with the chromatographic technique. The techniques have proved satisfactory for the purposes of identification and quantification of differentiation in barley samples analyzed. There was a chemical differentiation of the varieties of barley in relation to polyphenolic compounds identified and quantified and between varieties of different years of cultivation. In the assessment of climatic factors, it was observed that a lower average temperature, a higher rainfall and less sunshine received by barley between planting and harvest seasons, reflected in an increase of total phenols using the Folin-Ciocalteu and quantification of HPLC flavonoid rutin.
Os antioxidantes são compostos conhecidos por reagirem com radicais livres e/ou espécies reativas de oxigênio, de forma a inativá-los, prevenindo os danos oxidativos. Muitos estudos têm apontado para o desequilíbrio entre oxidantes e antioxidantes como o causador de muitas patologias, e devido à grande importância dada a este tema, existe uma forte demanda de estudos envolvendo a identificação e quantificação dos compostos com atividade antioxidante. O objetivo deste trabalho foi então quantificar e identificar os compostos polifenólicos de grãos integrais de cultivares brasileiras de cevada, cultivadas no município de Ibiaçá/RS, no ano agrícola de 2005 e 2006, provenientes do Centro de Pesquisa da Embrapa/Trigo, Passo Fundo/RS, e avaliar as condições climáticas (temperatura média, índice pluviométrico e insolação) entre a época de plantio e colheita da cevada na quantificação dos fenólicos totais entre as diferentes safras. As amostras foram caracterizadas quimicamente com relação à presença de polifenóis, empregando-se o método de separação baseado no sistema de cromatografia líquida de alta eficiência em fase reversa (RP-HPLC) com detecção UV-VIS a 254nm. Foram identificados os compostos fenólicos rutina, ácido caféico, ácido ferúlico, quercitrina e miricetina, sendo a rutina e o ácido caféico os mais abundantes entre as cultivares. Paralelamente foi realizada uma quantificação dos fenólicos totais pela técnica de Folin-Ciocalteu, visando uma comparação com a técnica cromatográfica. As técnicas mostraram-se satisfatórias para os objetivos de quantificação e identificação na diferenciação das amostras de cevada analisadas. Observou-se a diferenciação química das variedades de cevada com relação aos compostos polifenólicos identificados e quantificados e entre variedades de diferentes anos de cultivo. Na avaliação dos fatores climáticos, foi observado que uma menor temperatura média, um maior índice pluviométrico e uma menor insolação recebida pela cevada entre as épocas de plantio e colheita, refletiram em um aumento dos fenóis totais pelo método de Folin-Ciocalteu e na quantificação do flavonóide rutina por HPLC.
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Klatová, Kamila. "Stabilita a vlastnosti kombinovaných nápojů a ovocných koncentrátů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-376828.
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This diploma thesis deals with the stability and basic properties of combined beverages and fruit concentrates. The theoretical part describes the production and use of fruit concentrates. Furthermore, the work deals with anthocyanic pigments and phenolic substances. The principle and instrumentation of liquid chromatography and electron paramagnetic resonance were described. In the next subchapter, the methods of determination of total anthocyanins and phenolic substances were described. The experimental part of the thesis described the determination of soluble solids, viscosity and antioxidant activity. The total content of phenolic compounds were determined by the Folin-Ciocalteua method and the total anthocyanins were determined by the pH-differential method. In the samples were determined cyanidine-3-glucoside and cyanidin-3-galactoside by liquid chromatography.
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Balonková, Daniela. "Vybrané alkoholové extrakty bezu černého pro využití v kosmetologii." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-401938.
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This thesis focuses on the preparation of selected alcohol extracts of elderberry and their use in cosmetology. In the theoretical part are described the botanical properties of the elderberry (Sambucus nigra). There are introduced and characterized bioactive compounds and toxic compounds contained in all vegetative parts of the plant. Attention is mostly focused on compounds with antioxidant properties. The theoretical part also contains a description of basic analytical methods, which are used in the practical part to characterize compounds contained in elder flowers. The practical part focuses on the optimization of the preparation of alcohol extracts with the aim to prepare the extract with the greatest possible content of polyphenols with respect to economy and production costs. Factors such as selection of the appropriate solvent, solvent to plant material ratio, solvent temperature, and extraction time are examined. Based on the total polyphenol concentration measured spectrophotometrically by the Folin-Ciocalteu method, the most suitable solvent is 60% ethanol, the ratio of plant material to solvent is 1:8, the laboratory temperature of solvent and the extraction time of 24 hours.Under these conditions, an ethanol extract is prepared, analyzed and determined selected properties, such as refractive index and density. Rutin, chlorogenic, caffeic and ferulic acids are identified by HPLC with a DAD detector. The pH value of alcohol extract is 5.743 ± 0.006, the refractive index is 1.365 ± 0.02 at 22.7 ° C and the density is 0.9288 gcm-3. By liquid chromatography the concentration of chlorogenic acids is quantified as 0.104 gl-1, caffeic acid as 0.086 gl-1 and ferulic acid as 0.060 gl-1. The extract is incorporated into cosmetic products, that are used in balneology. Prepared products are toilet soap and bath salt.
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Damaschin, Igor. "Determinazione dei polifenoli nei vini: ottimizzazione di un metodo analitico basato su transistor elettrochimici organici." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16673/.
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In questo elaborato è stato sviluppato un metodo elettrochimico per la determinazione dei polifenoli nelle diverse tipologie di vino mediante l’utilizzo dei transistor elettrochimici a base organica, in cui la parte organica è formata dal polimero PEDOT:PSS. Si è cercato di ottimizzare le condizioni di migliore riproducibilità del segnale, come la tecnica elettrochimica, il tipo di elettrolita e il suo pH. In seguito, il metodo elettrochimico viene confrontato con quelli convenzionali per la determinazione dei polifenoli, in particolare, quelli spettrofotometrici. Il numero consistente dei campioni di diversi tipi di vino ha permesso di stabilire se i metodi elettrochimici e spettrofotometrici sono correlabili tra loro e di quanto.
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Ma, Sihui. "Discovery and dissemination of new knowledge in food science: Analytical methods for quantification of polyphenols and amino acids in fruits and the use of mobile phone-based instructional technology in food science education." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/100997.
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The discovery and dissemination of new knowledge are essential in food science. To advance our understanding of fruit chemistry, analytical methods were compared and applied.
Polyphenols are secondary metabolites in fruits of particular importance in food science, as they contribute to the sensory attributes and health benefits of the products. Evaluation of common analytical methods for the quantification of polyphenols, including the Folin-Ciocalteu (F-C), Lowenthal permanganate (L-P), 4-dimethylaminocinnamaldehyde (DMAC) and the bovine serum albumin (BSA) precipitation methods, was conducted using analytical method validation procedures. The F-C method was not specific to polyphenols, and the L-P method had the widest working range but lacked accuracy. The DMAC method was the most specific to flavanols, and the BSA method was not suitable for quantification of smaller flavanols. Quantitative performance of these four methods was evaluated using a broad range of fruit-derived samples. Variation in quantitative results obtained using these four methods was explained by differences in polyphenol and matrix composition of these samples and differences in operating principles of the methods.
The reactivity of individual polyphenol compounds (catechin, epicatechin, PC B2, PC pentamer, chlorogenic acid, phloretin, and quercetin) to the polyphenol and flavanol quantification results using Prussian blue (P-B), F-C, DMAC and BSA precipitation methods were also assessed and determined to differ by up to thirteen-fold, depending on the assay. Furthermore, the contribution and interactions of polyphenol compounds (catechin, PC B2, and chlorogenic acid) and potentially interfering compounds likely to be found in fruit and fruit products (ascorbic acid, glucose, and SO2) to the quantitative results of these methods were evaluated using a full factorial design. Significant interactions among polyphenol compounds, and among the interfering compounds were found. The standardized coefficient (β) for all factors and interactions of polyphenol compounds varied from 0.347 to 129, and from near 0 to -46.8 for all factors and interactions of interfering compounds. Our findings indicate that the choice of standards, polyphenol and matrix composition of the sample may cause disparity among the quantitative results of these methods.
Amino acids in apple (Malus × domestica Borkh.) juice not only influence the quality of fermented cider through fermentation kinetics but also impact the flavor of the cider through yeast metabolism. Due to recent advances in analytical instrumentation, amino acids profiles in apple juice were determined much faster and more accurately than by previously applied methods. Twenty amino acids were quantified by UPLC-PDA in juices from 13 apple cultivars grown in Virginia. The relative amino acid profile was significantly different among the apple juices evaluated. The total amino acid concentration ranged from 18 mg/L in Blacktwig juice to 57 mg/L in Enterprise juice. L-Asparagine, L-aspartic acid and L-glutamine are the principal amino acids observed in most apple juices. These results will inform future research on yeast metabolism and nitrogen management during cider fermentation.
To better disseminate knowledge gained through research to the next generation of food scientists, the effectiveness of new instructional technology—a cellphone-based personal response system—in food science education was evaluated. Students' academic performance was improved by the incorporation of this technology into lectures, and its use was well perceived by the students (easy to use and positively impacted their learning). This finding contributes to the scholarship of teaching and learning in food science by providing useful insight into the potential for application of such tools with improved student engagement and learning outcomes.
Advances in food chemistry research will enable the development of value-added food products, and the pedagogical advancement in food science education will better convey new and existing knowledge to students, who will apply this knowledge to promote a safe and nutritious food supply that enhances human health and increases the value of specialty crops.Doctor of Philosophy
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Santos, Gabriel Casimiro Lopes Silva. "Determinação de atividade antioxidante, compostos fenólicos totais e teor de resveratrol em cinco cultivares brasileiras de Arachis hypogaea L. com a utilização de duas metodologias extrativas." Universidade do Estado do Rio de Janeiro, 2013. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=5727.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorO amendoim A. hypogaea L. é a quarta oleaginosa mais consumida no mundo e suas sementes são altamente energéticas, com grandes quantidades de lipídios, proteínas, vitaminas e carboidratos. Diversas atividades farmacológicas já foram observadas em extratos de raízes, folhas e sementes, sendo a principal delas a atividade antioxidante. Neste trabalho, foi realizada a comparação entre duas metodologias (por maceração e assistida por micro-ondas) para a extração de compostos antioxidantes, incluindo o resveratrol. Também foi realizada a comparação entre extratos de diferentes órgãos de cultivares brasileiras (IAC 886, IAC Caiapó, IAC Tatu ST, IAC 8112 e IAC 99-1) quanto à atividade antioxidante, por DPPH, ao teor de compostos fenólicos, por Folin-Ciocalteu, e ao teor de resveratrol, por HPLC. Por fim, foram estabelecidos protocolos de cultura de tecidos para explantes de sementes, visando à produção de calos e plantas in vitro para posterior dosagem de compostos de interesse, tendo em vista a possibilidade de modulação das condições in vitro. As melhores condições determinadas para a extração por maceração de antioxidantes de A. hypogaea foram 80% de etanol em água como solvente, trituração com almofariz e pistilo, 50 mL solvente por grama de material vegetal seco, 120 minutos de incubação e dois estágios de extração. As melhores condições para a extração de resveratrol assistida por micro-ondas foram o uso de 37 mL de solvente/g material vegetal seco, com agitação de 1200 rpm por 15 minutos, a 37C. De uma maneira geral, os extratos de raízes e oriundos de micro-ondas apresentaram maior atividade antioxidante (até 92,36 2,71%), teor de compostos fenólicos (até 54,15 1,39 mg EAG/g extrato) e teor de resveratrol (até 1,614 0,356 mg/g extrato). Dentre as cultivares estudadas, IAC Tatu e IAC 99-1 foram as que apresentaram os teores mais elevados. Brotos e calos friáveis foram obtidos a partir de cotilédones, eixos embrionários e folíolos embrionários cultivados em meios suplementados com BAP e picloram, respectivamente.
Peanut A. hypogaea L. is the fourth most consumed oleaginous in the world and its seeds are high energetic, with high amounts of lipides, proteins, vitamins and carbohidrates. Several pharmacological activities have been observed in extracts of roots, leaves and seeds, especially an antioxidant activity. In this work, the comparison between two extraction methodologies (by maceration and microwave assisted extraction) for the extraction of antioxidant compounds, including resveratrol, was studied. We also carried out a comparison between extracts from different organs of Brazilian cultivars (IAC 886, IAC Caiapó, Tatu ST IAC, IAC 8112 and IAC 99-1) for antioxidant activity by DPPH, the content of phenolic compounds by Folin-Ciocalteu and the resveratrol content by HPLC. Finally, we established tissue culture protocols for seed explants, aiming at the production of in vitro plant material for future measurement of compounds of interest in the view of possible modulation of in vitro conditions. The best conditions for the extraction of antioxidant from A. hypogaea compounds by maceration were 80% of ethanol in water as a solvent, trituration by mortar and pestle, 50 mL solvent/g dry plant, 120 minutes of incubation and two stages of extraction. The best conditions for the extraction of resveratrol assisted by micro-wave were the use of 37 mL of solvent for each gram of dry plant, with 1200 rpm of agitation for 15 minutes, with 37oC. In general, root extracts and assisted by microwave showed higher antioxidant activity (until 92,36 2,71%), phenolic (untill 54,15 1,39 mg AGE/g extract) and resveratrol content (untill 1,614 0,356 mg/g extract). Among the studied cultivars, IAC Tatu and IAC 99-1 showed the best results. In tissue culture, shoots and friable calli were obtained from cotiledons, embryonic axis and embryonic leaflet cultured in media supplemented with BAP and picloram, respectively.
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Dalgê, Jéssica Jamila. "Estudo da capacidade antioxidante, antimicrobiana e anti-hemolítica do gengibre (Zingiber offinale)." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-08092015-083147/.
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O presente estudo teve como objetivo determinar a capacidade antioxidante, antimicrobiana e anti-hemolítica do gengibre (Zingiber officinale) utilizando diferentes solventes extratores. Para tal, rasuras secas de gengibre foram trituradas e usadas na proporção 1:50 (p/v) nas quatro diferentes extrações: água, etanol (70%), acetona/ácido acético (70%/2%) ou acetona (70%). Após centrifugação, o extrato foi utilizado pra determinar o conteúdo de compostos fenólicos por Folin-Ciocalteau e ação sobre os radicais ABTS+. e DPPH.. Foi selecionado o melhor solvente extrator pelas propriedades antioxidantes e facilidade de sua remoção da matriz. Este extrato foi submetido à rotaevaporaçao, liofilizaçao e ressuspenção em tampão fosfato salino (PBS) e, então, utilizado nos estudos biológicos de captura de NO, ação antioxidante sobre hemólise induzida e ação sobre o crescimento de S. aureus. Os resultados foram expressos como média e desvio padrão. Para análise estatística empregou o software Minitab® com comparação entre grupos por ANOVA, diferenças significativas por Tukey e P < 0,05. O extrato de gengibre obtido em acetona apresentou maior conteúdo de compostos fenólicos (8,52 ± 1,24 mg equivalente de ácido gálico/g de gengibre). O extrato acetona apresentou menor valor de EC50 e maior ação antioxidante mediantes o ensaio com ABTS+., sendo respectivamente 0,07 ± 0,01 mg de massa seca do extrato/mL de ensaio e 10,93 ± 0,79 mg equivalentes de trolox (ET)/g de gengibre, sem diferença significativa com os valores obtidos nos extratos etanol e acetona/ácido. No ensaio do DPPH., o extrato acetona apresentou menor valor de EC50 (0,15 ± 0,01 mg de massa seca de extrato/mL de ensaio) e maior ação antioxidante (8,35 ± 0,60 mg ET/g de gengibre), sem diferença significativa com relação ao extrato etanólico. Dentre todos os ensaios, a extração em água apresentou resultados menos satisfatórios. A acetona foi selecionada como solvente extrator dos componentes do gengibre para os estudos biológicos. O extrato de gengibre (17,25 mg de massa seca/mL) inibiu 50% da formação de produtos no ensaio de captura de NO, valor similar ao obtido pela presença do antioxidante ácido gálico. Concentrações menores de extrato também agiram sobre o NO, sendo que 1,25 mg/mL refletiu em 33% de inibição. A hemólise foi evitada em 100% pelo extrato de gengibre em concentrações acima de 113 µg de massa seca de extrato/mL, resultado similar ao encontrado no ensaio contendo ácido ascórbico. A lise das hemácias foi evitada em 44% na presença de extrato 57 µg/mL. O extrato de gengibre não apresentou ação antimicrobiana sobre S. aureus. Conclui-se o extrato de gengibre, nas condições deste estudo, apresenta atividade antioxidante sobre ABTS+. e DPPH.; bem como sobre sistemas biológicos modelos como na captura de NO e lise de membrana celular.The aim of this study was to determinate antioxidant capacity, antimicrobial activity and anti hemolytic action of ginger (Zingiber officinale) extract obtained by different solvents. For this purpose, dried ginger flakes were powdered and used in ratio 1:50 (w/v) in the four different extractions: water, ethanol (70%), acetone/acetic acid (70%/2%) and acetone (70%). The extract was centrifuged and used for phenolic compounds determination by Folin-Ciocalteau and action on ABTS+. and DPPH. radicals. The best extractor solvent was selected by its antioxidant properties and easier elimination from the matrix. The select extract was submitted on evaporation and lyophilization, and subsequent re-suspension on phosphate buffer saline (PBS). Then, this suspension was used in biologic studies as NO scavenging, antioxidant action on induced hemolysis and effect on S. aureus growth. The values were express as mean and standard deviation. Statistical analysis carried out by Minitab® using ANOVA and Tukey to p< 0.05. Acetone ginger extract showed highest value of phenolic content (8.52 ± 1.24 mg galic acid equivalent /g of ginger). The acetone extract showed the lowest EC50 value and higher antioxidant action on ABTS+., 0.07 ± 0.01 mg of dry weight of the extract/mL of assay and 10.93 ± 0.79 mg trolox equivalents (TE)/g of ginger, respectively. These values did not show significant difference in relation to ethanol and acetone/acid extracts. For DPPH. assay, acetone extract showed lower value of EC50 (0.15 ± 0.01 mg dry weight of extract/mL assay) and higher antioxidant action (8.35 ± 0.60 mg TE/g of ginger), without significant difference in relation to ethanolic extract. Among all extracts, aqueous extract showed lesser satisfactory results. Acetone extract was selected for biological assays. Ginger extract (17.25 mg of dry weigth/mL) inhibited 50% of products formation on NO scavenging assay, similarly to galic acid results. Lower extract concentrations as 1.25 mg/mL inhibited 33% of NO. The 100% of hemolysis prevention was obtained by concentrations of ginger extract higher than 113 µg of dry weight of extract/mL of assay. Similar result was observed by presence of ascorbic acid. Erythrocytes lysis was avoided in 44% by 57 µg/mL of ginger extract. Ginger extract did not show antimicrobial action on S. aureus. In conclusion, ginger extract, in present conditions, showed antioxidant action on ABTS+. and DPPH. assays and in biological model systems as in NO scavenging assay and cell membrane lysis.
Book chapters on the topic "Ciocalteu"
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Töpfer, G. "Folin-Ciocalteu-Methode." In Lexikon der Medizinischen Laboratoriumsdiagnostik, 1. Berlin, Heidelberg: Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/978-3-662-49054-9_1157-1.
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Töpfer, G. "Folin-Ciocalteu-Methode." In Springer Reference Medizin, 893. Berlin, Heidelberg: Springer Berlin Heidelberg, 2019. http://dx.doi.org/10.1007/978-3-662-48986-4_1157.
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Makkar, Harinder P. S. "Measurement of Total Phenolics and Tannins Using Folin-Ciocalteu Method." In Quantification of Tannins in Tree and Shrub Foliage, 49–51. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-017-0273-7_3.
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Lamuela-Raventós, Rosa M. "Folin-Ciocalteu method for the measurement of total phenolic content and antioxidant capacity." In Measurement of Antioxidant Activity & Capacity, 107–15. Chichester, UK: John Wiley & Sons, Ltd, 2017. http://dx.doi.org/10.1002/9781119135388.ch6.
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Mostafa, Mahrouz, Lahnine Lamyae, Mghazli Safa, Mourad Ouhammou, Mohammed Mouhib, and Moulay Ali Misdaq. "Case Study of Bacterial Decontamination of an Aromatic and Medicinal Plant: Decontamination of Thymus Satureioides by Gamma Radiation at Low Doses and Impact on Hygienic and Physicochemical Quality." In Alternative Medicine - Update. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.93521.
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The purpose of our study is to verify the usefulness of gamma irradiation treatment at low doses (0.25, 0.5 and 1 kGy) combined to vacuum packaging on commercial teas of Thymus satureioides deliberately contaminated with Escherichia coli. The efficiency and the influence of the process on contamination level and the shelf life of the product were studied. The phenolic composition and concentration were identified in the unirradiated and irradiated thyme. The total phenolic content (TPC) was assayed by the Folin-Ciocalteu method, the individual phenolic compounds were determined by high liquid chromatography (HPLC) and the essential oil was characterized by gas chromatography coupled to mass spectroscopy (GC-MS). The plant was observed by scanning electrons microscopy and the radioactivity effect was analyzed. The results show a complete decontamination of thyme depending to the dose and the storage time. Privileged hygienic quality was found in the irradiated thyme with the highest concentrations of polyphenols. The process showed the conservation of thyme quality without any alteration of its characteristics or radioactivity effect.
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Aguilar-Méndez, Miguel Ángel, Eduardo San Martín Martínez, Jorge Yáñez-Fernández, and Elisabeth Navarro-Cerón. "Nanoencapsulación de compuestos bioactivos con actividad antioxidante de Justicia spicigera (Muicle) y Theobroma cacao L. (Cacao)." In Avances de investigación en Nanociencias, Micro y Nanotecnologías. Volumen II, 29–46. OmniaScience, 2020. http://dx.doi.org/10.3926/oms.404.2.
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En este trabajo, se elaboraron nanopartículas cargadas con extractos polifenólicos de Theobroma cacao L. (cacao) y Justicia spicigera (muicle). El contenido de fenoles totales del grano de cacao y el muicle se determinó usando el reactivo Folin-Ciocalteu y la actividad antioxidante se estimó usando los ensayos DPPH (2,2-difenil-2-picrilhidrazilo) y FRAP (reducción férrica / poder antioxidante). El proceso de nanoencapsulación se realizó mediante un nano-secador por aspersión utilizando pectina y aislado de proteína de suero como materiales de pared. Los resultados mostraron que fue posible obtener nanopartículas con morfología esferoidal homogénea y un tamaño promedio de aproximadamente 500 nm. Los experimentos in vitro, en los que se utilizó el método DPPH para evaluar la prevalencia de la capacidad inhibitoria de radicales libres de los extractos nanoencapsulados, indicaron que las eficiencias de carga para las nanopartículas cargadas con ambos extractos fueron aproximadamente del 56.53 % y 41.38 % para muicle y cacao, respectivamente; de la misma manera los resultados de FRAP fueron equivalentes respecto a la capacidad antioxidante.
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Singleton, Vernon L., Rudolf Orthofer, and Rosa M. Lamuela-Raventós. "[14] Analysis of total phenols and other oxidation substrates and antioxidants by means of folin-ciocalteu reagent." In Oxidants and Antioxidants Part A, 152–78. Elsevier, 1999. http://dx.doi.org/10.1016/s0076-6879(99)99017-1.
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Kheiria, Hcini, Abidi Mounir, Quílez María, Jordán Maria José, and Sadok Bouzid. "Total Phenolic Content and Polyphenolic Profile of Tunisian Rosemary (Rosmarinus officinalis L.) Residues." In Natural Drugs from Plants [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.97762.
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Plants, especially herbs and spices, have always been the major sources of numerous natural compounds with antioxidant activity and other beneficial properties and, specifically, Rosemary (Rosmarinus officinalis L.) has been widely accepted as one of the spices with highest antioxidant activities which appear to be related to their richness of phenolic compounds. This study was undertaken with the aim to estimate the total phenolic content, identify and quantify the polyphenolic compounds of the methanolic extracts from post-distilled rosemary, collected from two different bioclimatic areas from Tunisia. Total phenolic content (TPC) was determined by Folin–Ciocalteu method. Identification and quantification of polyphenolic compounds was performed using high-performance liquid chromatography (HPLC) analysis. TPC ranged from 85.8 to 137.3 mg GAE/g DE in rosemary extracts. HPLC analysis showed the presence of carnosic acid and carnosol, wich were found to be the most abundant compounds in all analyzed extracts (46.3 to 76.4 and 22.4 to 43.5 mg/g of plant dry weight respectively), rosmarinic acid and caffeic acid as phenolic acids, besides some flavonoids such as apigenin, luteolin, genkwanin and hesperidin. This study revealed that rosemary post-distilled residues were shown to be promising with regard to their incorporation into various foods, cosmetics and fragrances.Therefore, supplementing a balanced diet with herbs may have beneficial health effects.
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Ikhiwili Oniha, Margaret, Eze Frank Ahuekwe, and Sharon Oluwatobi Akinpelu. "Phytochemical Contents of Essential Oils from Cymbopogon Species: A Tropical Medicinal Plant." In Tropical Plant Species and Technological Interventions for Improvement. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.105396.
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Natural resources especially medicinal plants possess the potentials to sustain all existence on earth. Cymbopogon, a globally cultivated herb, possesses high contents of diverse essential oils for medicinal and economic purposes including treatment of malaria and candidiasis. Notable species include Cymbopogon citratus and C. flexosus having citral as the main chemical compound. Numerous compounds of these species include limonene, citronella, geranyl acetic derivatives, elemol, among others. Phytochemical analysis of these essential oils is usually done by the gas chromatography-mass spectrometry (GC-MS) method sequel to obtaining them through solvent extraction, hydrodistillation, supercritical CO2 extraction, chromatography among others. Although the supercritical CO2 extraction method gives greater quality yields void of toxic wastes with preserved thermal stability compared with other methods, its high-working pressure generates issues of safety risks and costs. Quantitative determination is done using spectrophotometric, chromatographic, and Folin-Ciocalteu methods. In comparison with other chromatographic techniques employed, gas chromatography exhibits greater efficiency by quantifying and determining the presence of various components at low concentrations. This prominently economical plant with potent ethnobotanical benefits hinged on the essential oils phytochemicals is faced with diverse extraction challenges; thus, improvement in the extraction and quantification techniques is key to the harvest of pure yields of lemon grass essential oils.
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Rodríguez Jiménez, Daniela Yusbizareth, Candy Andreina Montaño Pérez, Martha Edith Cancino Marentes, Rogelio Fernández Argüelles, Javier German Rodríguez Carpena, and Gabriela María Ávila Villarreal. "COMPARACIÓN DEL CONTENIDO FENÓLICO EN MUESTRAS DE TÉ NEGRO Y VERDE COMERCIALES MEDIANTE EL MÉTODO DE FOLIN–CIOCALTEU." In Estudos em Ciências Exatas e da Terra: Desafios, Avanços e Possibilidades, 18–23. Editora Artemis, 2023. http://dx.doi.org/10.37572/edart_2402237433.
Full textConference papers on the topic "Ciocalteu"
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Walker, Richard B., Jace D. Everette, Quinton M. Bryant, Ashlee M. Green, Yvonne A. Abbey, Grant W. Wangila, and Olga Tarasenko. "REACTIVITY OF VARIOUS COMPOUND CLASSES TOWARDS THE FOLIN-CIOCALTEU REAGENT." In BIOLOGY, NANOTECHNOLOGY, TOXICOLOGY AND APPLICATIONS: 4th BioNanoTox (Biology, Nanotechnology, Toxicology) and Applications. AIP, 2010. http://dx.doi.org/10.1063/1.3419685.
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Ezenarro Garate, Jokin, Ane Bordagaray Eizagirre, and Rosa Mª Garcia Arrona. "Infusioen ahalmen antioxidatzailearen determinazioa Folin-Ciocalteu erreakzioa eta irudi digitalen analisi bidez." In IV. Ikergazte. Nazioarteko ikerketa euskaraz. Bilbao: UEU arg, 2021. http://dx.doi.org/10.26876/ikergazte.iv.05.11.
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Arshanitsa, Alexandr, Jevgenija Ponomarenko, Maris Lauberts, Vilgelmina Jurkjane, Lilija Jashina, Alexandr Semenischev, Jegor Akishin, and Galyna Telysheva. "Composition of extracts isolated from black alder bark by microwave assisted water extraction." In Research for Rural Development 2020. Latvia University of Life Sciences and Technologies, 2020. http://dx.doi.org/10.22616/rrd.26.2020.013.
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The composition of extracts isolated from black alder bark by ‘green’ microwave assisted water extraction in the temperature range of 70–150 ℃ was studied using the wet chemistry Folin-Ciocalteu method and Py-GC-MS/FID. The composition data were compared with those of the extracts obtained at the same temperature by accelerated solvent extraction (ASE) of bark. It was shown that microwave assisted extraction, compared with ASE, resulted in more significant transition of major cell wall components, including hemicelluloses and phenolics of lignin origination, into the solution. Depending on the microwave assisted extraction regimes, products with different portion of major cell wall components and secondary phenolic metabolites can be isolated that enlarge the possibilities of products valorisation. Thus, a significant promotion of secondary phenolic metabolites’ transition into extracts as a result of microwave extraction was observed at 70 ℃. At that time the relative portion of carbohydrates in extracts was increased at high temperature extraction, combining dynamic and isothermal microwave heating. Water extraction of black alder bark in a microwave extractor revealed 25–50% lower specific energy consumption and 1.8–2.6 times higher productivity in comparison with the conventional extraction, that is beneficial in view of the upscale and practical application of this innovative biomass processing.
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Vidal, Eduardo, Rocío Sierra Ramírez, and Luis Jorge Cruz Reina. "Recuperación de compuestos fenólicos de la pulpa del café por medio de una percolación a través de un extractor Soxhlet en escala piloto." In Nuevas realidades para la educación en ingeniería: currículo, tecnología, medio ambiente y desarrollo. Asociación Colombiana de Facultades de Ingeniería - ACOFI, 2022. http://dx.doi.org/10.26507/paper.2312.
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Entre los múltiples residuos generados por la producción cafetera destaca la pulpa o cereza del fruto, la cual es responsable por cerca del 30% del peso en base seca del total del grano. La pulpa del café ofrece diferentes compuestos químicos de alto interés para la industria alimenticia y farmacéutica, donde destacan los compuestos fenólicos disponibles en esta, en especial los Ácidos Clorogénico, Cafeico, Ferúlico y Cumárico. Se realizó una extracción de los compuestos fenólicos por medio de una percolación en un equipo Soxhlet para evaluar el impacto del tipo de solvente, el tiempo de extracción y la relación de pulpa:solvente en el contenido de fenoles totales (TPC) del extracto. Se caracterizó el TPC de los 30 extractos realizados usando el método de Folin-Ciocalteu usando Ácido Gálico para la curva de calibración. Se encontró una influencia significativa en el TPC de cada extracto por el tipo de solvente utilizado en la extracción, mientras que los otros dos factores no fueron estadísticamente significativos. Se obtuvo un rendimiento máximo de de contenido de polifenoles por gramo de pulpa usado en la extracción utilizando Etanol al 95% de pureza. Se discute una oportunidad industrial en la extracción de los mencionados compuestos de la pulpa de café, donde los rendimientos alcanzados ofrecen un valor agregado al residuo, pudiendo beneficiar a la agroindustria cafetera con ingresos adicionales para los caficultores.
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Bordean, Despina-Maria, Aurica Breica Borozan, Gabriel Bujanca, Camelia Cioban, and Delia Gabriela Dumbrava. "EFFECTS OF BOILING AND ROASTING ON CRUDE PROTEINS, TOTAL ANTIOXIDANT CAPACITY AND TOTAL POLYPHENOLS CONTENT OF POTATO TUBERS." In GEOLINKS International Conference. SAIMA Consult Ltd, 2020. http://dx.doi.org/10.32008/geolinks2020/b1/v2/08.
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Compared with other sources, potato can bring multiple nutritional benefits because it’s naturally low energy food (0.7 kcal), having high water, fiber and starch content. Even if the consummation of potatoes is in decline, it is still considered a source of valuable nutrition. Depending on the method of preparation, potatoes contain significant level of proteins and antioxidants and can offer considerable protection against cardiovascular diseases and cancer. Natural antioxidants are present under different forms in all plants, being the base source of these compounds for humans. The objective of this study was to determine the moisture content, crude protein, total antioxidant capacity and phenolic content of three assortments of potatoes (Solanum tuberosum) available on the Romanian local market (Timis County). The study was carried out on raw, unpeeled, boiled and roasted potatoes. The moisture content was determinate thermogravimetrically using Sartorius thermo balance, crude protein quantified by using a rapid colorimetric method, total antioxidant capacity determinate using CUPRAC method and total polyphenols content using Folin-Ciocalteu assay. The experimental results show that blue roasted potatoes present the highest content of crude protein, total antioxidant capacity and total polyphenols content and the lowest water content. The obtained data are used to create a graphical fingerprint of raw and processed potatoes in order to identify the best options to mix different potatoes assortments and to create innovative nutritious food products
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MARTINS, JEOVANA THAYNARA OLIVEIRA, ELAINY CRISTINY CHAVES PINHEIRO, ALANA DA CONCEIçãO BRITO COELHO, BIANCA FERREIRA BORGES, DANIELLE ANDREA PEREIRA COZZANI CAMPOS, MáRCIA CRISTINE SANTOS MACEDO, ALAMGIR KHAN, and RAQUEL MARIA TRINDADE FERNANDES. "AVALIAÇÃO DA ATIVIDADE ANTIOXIDANTE DOS EXTRATOS VEGETAIS DAS FOLHAS DA ESPÉCIE Mangifera indica Linneaus." In II Brazilian Congress of Development. DEV2021, 2021. http://dx.doi.org/10.51162/brc.dev2021-0097.
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Ao longo dos séculos, as pesquisas químicas e farmacêuticas, mostram possibilidades em curas e tratamentos de doenças, introduzindo a utilização de plantas de forma medicinal por fácil obtenção e, pela grande tradição de uso de plantas medicinais. Entre as plantas convencionais, que vem se destacando atualmente, está a Mangifera indica Linneaus. Essa planta é rica em compostos antioxidantes, capaz de auxiliar no envelhecimento celular e doenças relacionadas, tais como: as inflamações, aterosclerose, diabetes e doenças neurológicas, reduzindo os riscos de câncer e doenças cardiovasculares, podendo diminuir as reações de oxidação nocivas ao corpo humano. Nesse trabalho, foi utilizado o extrato das folhas da mangueira, da variação Manga Comum, utilizando o método espectrofotométrico na região do visível (760 nm), utilizando o reagente de Folin-Ciocalteu. O teor de fenóis totais, determinado em relação a uma curva de calibração com ácido gálico, foi de 23,08 ± 2,09 mg de EAG / g do extrato bruto das folhas de Mangifera indica. A atividade antioxidante foi expressa em CI50 (concentração inibitória), que foi definida como a concentração (µg mL-1) da amostra necessária para inibir a concentração inicial de DPPH em 50 %. O extrato bruto das folhas de Mangifera indica apresentou uma boa atividade antioxidante com IC50 de 63,28 ± 0,93 µg mL-1. Concluindo assim que, as folhas de Mangifera indica são uma fonte potencial de compostos antioxidantes.,
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Pavlović, M., Z. Simić, and Gorica Đelić. "DETERMINATION OF HEAVY METALS AND SECONDARY METABOLITES OF „PEUCEDANUM OREOSELINUM“ (APIACEAE)." In 1st INTERNATIONAL Conference on Chemo and BioInformatics. Institute for Information Technologies, University of Kragujevac, 2021. http://dx.doi.org/10.46793/iccbi21.206p.
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The total quantity of metals (Mg, Ca, Ni, Fe, Mn, Zn, Cu) in soil samples and in sixteen different extracts from plant parts of Peucedanum oreoselinum (L.) Moench as well as the content of total phenols and flavonoids in plant extracts was determined. The contents of metals were determined by the atomic absorption spectrometer. Based on the average values of the metal concentration in the soil, they could be arranged in the following sequence: Fe > Ca > Mg > Mn > Zn > Cu > Ni. Soil concentrations of all tested metals were lower than the maximum allowed concentration. The results demonstrated that the analyzed plant extracts contained higher quantities of Ni and Ca. Although the studied species accumulate analyzed metals in different quantities, they are not hyperaccumulators of these metals. Total phenols were determined using Folin-Ciocalteu reagent and their amounts ranged from 1.94 to P. oreoselinum, hyperaccumulation, phenols, flavonoids32.38 mg GA/g. The amounts of flavonoids in plant extracts were in range from 0.69 to 25.83 mg RU/g. We examined the correlation of metals and the phenolic compounds content in the extracts. According to our results the use P. oreoselinum for tea preparation is safe to a great extent for people, because in spite of the determined metal absorption by plant organs, the tea does not contain dangerous quantity of heavy metals. Also, it is suitable for the preparation of teas and herbal extracts due to minimal content of toxic metal (Ni), phenols and flavonoids.
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Zhao, Hefei, and Selina Wang. "Isolation and purification phenolic compounds in California olive pomace by pilot-scale C18 gel chromatography." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/hkjz6249.
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According to the Food and Agriculture Organization, the United States (mainly in California) produced 151,950 tons of olives in 2019, which resulted in a large amount of pomace waste. While many researchers focused on crude extraction and macroporous resin purification from European olive pomace on an analytical scale, few studies have been conducted to isolate fractions of US olive pomase (OP) by pilot-scale C18 chromatography. Hexane defatted Arbequina California OP was extracted by water, and the extract was loaded to a pilot-scale chromatography column with 262.5 mL C18 gel, and the elute syrup (ES) was collected. Desorptions were applied by 1 L of acidified water (AW), 35% methanol (35M) and 70% methanol (70M), respectively. The fractions were concentrated then freeze-dried. Total phenol contents (TPC) were measured by Folin-Ciocalteu assay. Individual phenols were determined by HPLC-DAD. Results showed that the TPC of the fractions of ES, AW, 35M and 70M were 2.88, 29.39, 170.56 and 235.96 mg gallic acid equivalents/g, respectively. Heatmap cluster analysis showed that ES and AW fractions had similar phenol profiles with hydroxytyrosol and tyrosol-glucoside; and 35M had hydroxytyrosol-glucoside, hydroxytyrosol, tyrosol-glucoside, 4-hydroxyphenylacetic acid (4-HPA), verbascoside and oleuropein; 70M contained hydroxytyrosol, tyrosol-glucoside, tyrosol, but generally had more nonpolar compounds such as verbascoside, rutin and oleuropein. Very interestingly, the 3,4-DHPEA-EDA in water extract at 31.43 min disappeared in 35M and 70M fractions, meanwhile a new peak at 29.25 min showed up which could be a new compound derived from 3,4-DHPEA-EDA possibly because of the acidified process. This study could be the first-ever report of phenol profile of pilot-scale C18 fractions of the US OP. This new data on the chemical compositions of the OP C18 fractions provides practical knowledge for the valorization and industrial food applications of the US olive wastes.
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Rodríguez-Ramírez, Juan, Irene Chaparro-Hernández, Lilia L. Méndez-Lagunas, and Luis Gerardo Barriada-Bernal. "Effect of spray drying conditions on antioxidants activity, flavonoids and total phenolic compounds of stevia rebaudiana." In 21st International Drying Symposium. Valencia: Universitat Politècnica València, 2018. http://dx.doi.org/10.4995/ids2018.2018.7518.
Full textAbstract:
In this work the spray drying of the fresh stevia leaves aqueous extract without encapsulating agents was carried out. The effect of the inlet air temperature (160-200 ºC) and the feed flow rate (2-3 kg/h) on the total phenolic content, the total flavonoid content and the antioxidant capacity were evaluated using Folin-Ciocalteau, aluminum chloride and DPPH methods respectively. The inlet air temperature had a significant effect on all parameters evaluated that showed a decrease when increasing the inlet air temperature, the feed flow rate had a significant effect on total flavonoids content and the antioxidant capacity, by increasing the feed flow rate the inhibition of the DPPH radical decreased and the total flavonoid content increased. The treatment at 160 ºC and 3 kg/h retained highest total flavonoid content and the antioxidant capacity. Keywords: Phenolic compounds, stevia, spray drying, antioxidant capacity
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"Determination of Antioxidant Property, Total Phenolics Content, and α-Glucosidase Inhibitory Activity of Different Solvent Extracts of Defatted and Non-Defatted Peanut Skins." In 4th International Conference on Biological & Health Sciences (CIC-BIOHS’2022). Cihan University, 2022. http://dx.doi.org/10.24086/biohs2022/paper.781.
Full textAbstract:
Peanut skins are by-product with little economic value. The effect of different solvents, on the total phenolic content (TPC), antioxidant property and in vitro antidiabetic activity of defatted and non-defatted peanut skins was determined. TPC was estimated using Folin-Ciocalteau reagent. Antioxidant property was evaluated using ferric reducing antioxidant power (FRAP) and 2, 2-diphenyl-1- picrylhydrazyl (DPPH) radical scavenging capacity methods, α-glucosidase inhibition was evaluated using 4- nitrophenyl α-D-glucopyranoside (pNPG) method. Peanut skin of the defatted extracted with ethanol had the much of the content of total phenolics (391.76 mg/g GAE). Highest DPPH scavenging property was found in the methanolic extract of defatted peanut skins with IC50 value of 15.00 ± 1.00 μg/mL, while highest FRAP value was found in the aqueous extract of non-defatted extracts. Aqueous extracts demonstrated stronger inhibitory property against α-glucosidase and had IC50 of 16.33 ± 1.15 and 16.33 ± 8.50 μg/mL for defatted and non-defatted extracts, respectively. The finding of the present shows that peanut skins are important by-product for utilization as natural antioxidant and α-glucosidase inhibitors.
Reports on the topic "Ciocalteu"
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Swita, Marie, Teresa Lemmon, Ruoshui Ma, Joshua Taylor, Asanga Padmaperuma, Mariefel Olarte, Earl Christensen, and Jack Ferrell III. Determination of Phenolic Groups in Bio-Oils Using Revised Folin-Ciocalteu Methods: Single Cuvette and Plate Reader. Laboratory Analytical Procedure (LAP), Issue Date: May 12, 2022. Office of Scientific and Technical Information (OSTI), May 2022. http://dx.doi.org/10.2172/1868495.
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