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Estudo da capacidade antioxidante, antimicrobiana e anti-hemolítica do gengibre (Zingiber offinale) / Study of antioxidant capacity, antimicrobial activity and anti hemolytic action of ginger (Zingiber officinale)Dalgê, Jéssica Jamila 28 March 2014 (has links)
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.
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Estudo da capacidade antioxidante, antimicrobiana e anti-hemolítica do gengibre (Zingiber offinale) / Study of antioxidant capacity, antimicrobial activity and anti hemolytic action of ginger (Zingiber officinale)Jéssica Jamila Dalgê 28 March 2014 (has links)
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.
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Vliv oxidu siřičitého na vybrané kvalitatívní parametry vínaVarmuža, Radek January 2016 (has links)
This thesis dealing with The influence of sulfur dioxide on on qualitative parameters of the wines was developer between 2014/2016 at the Department of Post Harvest Technology of Horticultural Products, Faculty of Horticulture, Mendel University in Brno. In this thesis was studied influence of sulfur dioxide on total polyphenols, which was measured by Folin-Ciocalteu and antioxidant capacity, which was measured by FRAP and DPPH. For this experiment were chosen two wines. The white wine was Rulandské bílé and the red wine was Svatovavřinecké. Doses of sulfur dioxide were applied at 0 mg/l, 25 mg/l, 50 mg/l, 75 mg/l, 100 mg/l. These doses are used in winemaking. Was found, that sulfur dioxide added to wine influence measured values of polyphenols and antioxidant capacity measured by FRAP and DPPH. Also was found, that system FRAP is more affected by sulfur dioxide, than system DPPH.
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Managing Apple Maturity and Storage to Increase the Quality of Virginia Hard CidersEwing, Brianna Leigh 03 February 2017 (has links)
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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Análise de pigmentos fotossintetizantes e substâncias fenólicas em Gracilariopsis tenuifrons (C. J. Bird & E. C. Oliveira) Fredericq & Hommersand em diferentes intensidades de luz / Analysis of photosynthetic pigments and phenolic compounds in Gracilariopsis tenuifrons (C.J. Bird & E.C. Oliveira) Fredericq & Hommersand at different light intensitiesTorres, Priscila Bezerra 03 August 2012 (has links)
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 antioxidantes / The 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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Determinação eletroanalítica e espectrofotométrica da atividade antioxidante de fermentados de jabuticaba e vinhos de diferentes procedências / Voltammetric and spectrofotometric analysis of fermented beverages of jabuticaba and wines of diferent originsSá, Luísa Zaiden Carvalho Martins de 28 March 2013 (has links)
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Previous issue date: 2013-03-28 / 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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Análise de pigmentos fotossintetizantes e substâncias fenólicas em Gracilariopsis tenuifrons (C. J. Bird & E. C. Oliveira) Fredericq & Hommersand em diferentes intensidades de luz / Analysis of photosynthetic pigments and phenolic compounds in Gracilariopsis tenuifrons (C.J. Bird & E.C. Oliveira) Fredericq & Hommersand at different light intensitiesPriscila Bezerra Torres 03 August 2012 (has links)
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 antioxidantes / The 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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Vliv kuchyňských úprav na obsah fenolických látek v miříku celeru (Apium graveolens) / Influence of kitchen treatments on the content of phenolic substances in celery (Apium graveolens)ŠIROKÁ, Johana January 2019 (has links)
Phenolic substances were detected in the celery (Apium graveolens) in three species. Monitoring the phenolics were accomplished in the raw state of the plant, in the plant that was cooked, in the stock and in the dried state. In this master´s thesis are summarized results that were measured, methodology relating to the measurement as well as a description of cultivation of those plants. From the results arise that the smallest amount of phenolic substances has an extract from cooked celery. The biggest amount of phenolic substances is in the raw celery´s stalk as well as in the dried celery. In the celery were identified another three phenolics - Apigenin, Kaempferol, and Lureolin.
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CARACTERIZAÇÃO DE COMPOSTOS ANTIOXIDANTES EM GRÃOS DE DIFERENTES CULTIVARES DE CEVADA (Hordeum vulgare L.) / CHARACTERIZATION OF ANTIOXIDANTS COMPOUNDS IN GRAINS OF DIFFERENT BARLEY CULTIVARS (Hordeum vulgare L.)Bezerra, Aline Sobreira 29 January 2009 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Antioxidants 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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Vybrané alkoholové extrakty bezu černého pro využití v kosmetologii / Selected alcohol extracts of Sambucus nigra for use in cosmetologyBalonková, Daniela January 2019 (has links)
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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