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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Avaliação clínico-laboratorial dos possíveis efeitos deletérios dos polifenois no terceiro trimestre de gestação / Clinical and laboratorial evaluation of the possible deleterious effects of polyphenols in the third trimester of pregnancy

Bubols, Guilherme Borges January 2013 (has links)
Os polifenois são normalmente considerados compostos que apresentam atividades biológicas promissoras, em especial pelos seus efeitos antioxidantes e anti-inflamatórios. No entanto, estudos recentes têm demonstrado que o consumo materno de alimentos ricos em polifenois (ARP) durante a gestação interfere na dinâmica de fluxo do ductus arteriosus (DA) no coração fetal de humanos, provavelmente pelo efeito anti-inflamatório dos polifenois, e também tem sido demonstrado que a restrição da ingestão de ARP é capaz de reverter a constrição ductal. Neste trabalho, um estudo experimental foi desenvolvido com ovelhas prenhas, no qual os animais receberam suplementação oral de polifenois durante 14 dias. Realizou-se ecocardiografia fetal e a análise de amostras de sangue e urina para investigar biomarcadores de estresse oxidativo e inflamação além da excreção de polifenois totais na urina. Houve aumento nas velocidades sistólicas (VS) e diastólicas (VD) e uma diminuição no índice de pulsatilidade (IP), o que indica uma constrição prematura do DA após o consumo de polifenois. Houve diminuição da peroxidação lipídica, determinada pelos níveis de TBARS, e nos níveis de tióis reduzidos não proteicos após o tratamento. Houve um aumento das atividades das enzimas catalase (CAT) e glutationa peroxidase (GPx) após o tratamento. Apesar do não envolvimento de dano lipídico na constrição ductal, observou-se um aumento no dano proteico através da dosagem de proteínas carboniladas (PCO). O efeito vasoconstritor e anti-inflamatório foi verificado pela diminuição nos níveis de nitritos/nitratos (NOx) após o consumo de polifenois. O estresse oxidativo estava associado com parâmetros de constrição ductal, através das correlações de dano protéico (PCO) com VS (r=0,629, p=0,028), VD (r=0,905, p=0,0001) e IP (r=-0,772, p= 0,003). Ainda, VS foi correlacionada com catalase (r=0,672, p=0,033) assim como IP com GPx (r=-0,629, p= 0,05). A constrição ductal estava ainda associada com o parâmetro inflamatório, sendo VS e VD correlacionadas com NOx (r=-0,853, p=0,0004 e r=-0,705, p=0,010, respectivamente) além da correlação entre IP e NOx (r=0,599, p=0,039). Além disso, ambos os mecanismos anti-inflamatórios e antioxidantes estavam correlacionados: NOx e GPx (r=-0,755, p=0,004) e entre NOx e catalase (r=-0,812, p=0,001), confirmando a ocorrência de ambos efeitos atribuíveis aos 10 polifenois. Neste estudo, foi possível perceber que um elevado consumo de polifenois induziu constrição ductal em ovelhas prenhas com uma excreção urinária aumentada de polifenois totais e alterações em biomarcadores de estresse oxidativo e inflamação. Estes resultados ressaltam a necessidade de uma orientação dietética ao final da gestação com relação ao consumo de alimentos ricos em polifenois devido à possibilidade de indução de constrição ductal através da ação anti-inflamatória em fetos expostos. / Polyphenols are often referred to as compounds with promising biological activities, especially antioxidant and anti-inflammatory effects. However, it has been recently reported that maternal consumption of polyphenol-rich foods (PRF) interferes with ductus arteriosus (DA) flow in human fetuses’ hearts, probably by an anti-inflammatory effect and it has also been shown that restriction of PRF ingestion reverses ductal constriction. In this work, an experimental study was carried out with pregnant sheep, in which the animals received oral polyphenol supplementation for 14 days. Fetal echocardiography was performed along with blood and urine analysis to investigate antioxidant and anti-inflammatory biomarkers and total polyphenol (TP) urinary excretion. We found a decrease in lipid peroxidation by TBARS levels and a decrease in non-protein reduced thiols after treatment. In addition, an increase in enzymatic activities of catalase (CAT) and glutathione peroxidase (GPx) was observed. Despite that lipid peroxidation was not involved in ductal constriction, protein damage by enhanced protein carbonyls (PCO) were found. Anti-inflammatory and vasoconstrictive effects were observed by a decrease in nitrites/nitrates (NOx) in pregnant sheep after polyphenol consumption. Oxidative stress was associated to ductal constriction parameters, according to the correlations.of protein damage marker PCO to SV (r=0.629, p=0.028), VD (r=0.905, p=0.0001) and IP (r=-0.772, p=0.003). Also, SV was positively correlated to CAT (r=0.672, p=0.033) and IP negatively correlated to GPx (r=-0.629, p=0.05). Ductal constriction was also associated to the inflammatory parameter, due to the correlations of SV and DV to NOx (r=-0.853, p=0.0004 and r=-0.705, p=0.010, respectively) as well as the correlation between IP and NOx (r=0.599, p=0.039). Besides, association of both inflammatory and antioxidant mechanisms were found: NOx vs. GPx (r=-0.755, p=0.004) and NOx vs. CAT (r=-0.812, p=0.001), confirming the presence of both effects attributed to polyphenols. We report that high polyphenol intake induced fetal DA constriction in pregnant sheep followed by an increased TP excretion and alterations in inflammatory and oxidative biomarkers. These results highlight the need for a dietary orientation in late-pregnancy regarding maternal intake of foods with high polyphenol contents in light of the possible induction of ductal constriction through an anti-inflammatory action of polyphenols in exposed fetuses.
142

Microencapsulamento de compostos bioativos da uva (Vitis labrusca L.) e efeito do tratamento pós-colheita com UV-C em uvas Bordô

Kuck, Luiza Siede January 2016 (has links)
O Rio Grande do Sul é o maior produtor de uvas do Brasil, e as cultivares de Vitis labrusca representam mais de 90% da produção, dentre as quais se destacam as variedades Isabel e Bordô, que se caracterizam por conter altas concentrações de polifenóis, principalmente antocianinas, que exibem propriedades antioxidantes e que podem ser usados como corantes em alimentos. Entretanto, a utilização destes compostos em alimentos se torna difícil devido à sua alta instabilidade, e uma das formas de proteger estes compostos das condições adversas do meio é a microencapsulação. O bagaço da uva, proveniente da fabricação de sucos e vinhos, contém uma elevada concentração de polifenóis, e é composto em grande parte pela casca da uva. Dessa forma, este trabalho de Tese, teve como primeiro objetivo a extração dos polifenóis da casca das uvas Isabel e Bordô, e seu microencapsulamento utilizando diferentes materiais de parede, o qual foi dividido em três etapas. Na primeira etapa, foi realizada a separação dos compostos fenólicos mediante extração aquosa em meio ácido da casca de uva Isabel. A seguir, o extrato foi submetido à atomização para obtenção das micropartículas, utilizando goma arábica, β-ciclodextrina e hidroxipropil-β-ciclodextrina como agentes encapsulantes, combinadas em concentrações máximas de 5%. Os pós obtidos foram avaliados quanto aos fenóis totais, antocianinas monoméricas totais, flavonoides, flavanols, atividade antioxidante (DPPH, CUPRAC e HRSA), cor, umidade, atividade de água, solubilidade, higroscopicidade, temperatura de transição vítrea e microestrutura. De forma geral, os pós obtidos apresentaram alta higroscopicidade e baixa temperatura de transição vítrea, além de aglomeração das partículas. O tratamento elaborado com 3% de goma arábica e 2% de β-ciclodextrina foi considerado o melhor, com maior retenção de flavonoides (67,2%), flavanols (51,1%), atividade antioxidante por DDPH (55%) e CUPRAC (58,8%), menor higroscopicidade (17,33%) e maior temperatura de transição vítrea (32,85 °C). Na segunda etapa, o extrato fenólico aquoso acidificado da casca de uva Bordô foi atomizado e liofilizado para a obtenção das micropartículas, utilizando goma arábica, goma guar parcialmente hidrolisada e polidextrose, em um total de 10% de material de parede. Os pós obtidos foram avaliados quanto ao conteúdo de fenóis totais, antocianinas monoméricas totais, atividade antioxidante (DPPH, CUPRAC, HRSA), cor, umidade, atividade de água, solubilidade, higroscopicidade, temperatura de transição vítrea, tamanho de partícula e microestrutura. Foram obtidas altas retenções, maiores que 80% para fenóis totais e antocianinas monoméricas totais, e entre 45 e 84% para atividade antioxidante em todos os tratamentos estudados. Os pós atomizados tiveram menor umidade, atividade de água e tamanho de partícula, maior solubilidade e temperatura de transição vítrea, além de melhores características morfológicas do que os pós liofilizados. O pó obtido por atomização com 5% de goma guar parcialmente hidrolisada e 5% de polidextrose foi considerado o melhor tratamento, visto que teve maior retenção de fenóis totais (89,0%), antocianinas monoméricas totais (99,5%) e atividade antioxidante por DPPH (57,3%) e CUPRAC (83,2%). Na terceira etapa, dispersões de extrato de casca de uva Bordô com 5% de goma guar parcialmente hidrolisada e 5% de polidextrose, que foi considerado o melhor tratamento dentre todos os elaborados com uva Isabel e Bordô, foram atomizadas e liofilizadas para obtenção das micropartículas, que foram submetidas a testes acelerados de armazenamento (umidades relativas de 75 e 90% em temperaturas de 35, 45 e 55 °C) e de simulação de digestão gastrointestinal (divididos em duas fases: fase gástrica e fase intestinal). Foram avaliados os conteúdos de fenóis totais, antocianinas monoméricas totais e atividade antioxidante por ABTS. Quanto às provas aceleradas, a temperatura teve um efeito significativo na diminuição no conteúdo de fenóis, com retenções de 82,5% a 93,5%. Na redução do conteúdo de antocianinas monoméricas totais foi significativo o efeito da temperatura, umidade relativa e tempo, com retenções de 3,9 a 42,3%. A redução do teor de antocianinas monoméricas totais exibiu cinética de primeira ordem, e os valores de z e Ea indicaram que o pó liofilizado é mais instável às mudanças de temperatura, quando utilizadas temperaturas mais elevadas. Por outro lado, os valores de D e t1/2 foram muito próximos entre os dois pós, o que indica pouca diferença de estabilidade entre eles nas temperaturas utilizadas neste estudo. Os parâmetros termodinâmicos indicaram que a reação foi endotérmica e não espontânea. A atividade antioxidante teve comportamento similar ao dos fenóis totais, com retenção final de 38,5 a 59,5%. Quanto à simulação da digestão gastrointestinal os dois pós tiveram liberação de fenóis de aproximadamente 80% na fase gástrica, e aumento significativo da liberação na fase intestinal, onde, na última hora de experimento, o pó atomizado teve 90,6% de liberação e o liofilizado 94,9%. Comportamento similar foi observado para a atividade antioxidante, onde o pó atomizado e o pó liofilizado tiveram percentuais próximos a 50% na fase gástrica e aumento significativo na fase intestinal, onde na última hora do experimento o pó atomizado teve 69,4% da atividade antioxidante e o pó liofilizado 67,8%. Entretanto, as antocianinas monoméricas tiveram redução significativa de aproximadamente 50% do seu conteúdo na fase intestinal, onde, na última hora de experimento, o pó atomizado teve 39% de liberação e o liofilizado 39,8%. O método de obtenção das micropartículas não influenciou na estabilidade dos pós, tanto nos testes acelerados de armazenamento quanto na simulação da digestão gastrointestinal. Como segundo objetivo foi avaliado o efeito da irradiação UV-C em uvas Bordô, como tratamento pós-colheita. Foram estudadas duas safras de anos diferentes, sendo que na primeira as uvas foram submetidas a 0, 0,5, 1, 4, 10 e 30 minutos de irradiação (120 W) e armazenadas a 22 °C, enquanto que na segunda safra as uvas foram submetidas à irradiações com UV-C (120 W) por 0, 0,5 e 4 minutos, combinada com ultrassom (40 kHz) por 5 minutos e armazenadas a 22 °C. Na primeira safra, as uvas não apresentaram aumento dos compostos bioativos e da atividade antioxidante. Entretanto, na segunda safra, os resultados indicaram o aumento significativo no conteúdo de fenóis totais, antocianinas monoméricas totais e na atividade antioxidante para as uvas irradiadas por 0,5 minutos com UV-C e para as irradiadas com UV-C por 4 minutos em combinação com ultrassom por 5 minutos, com aumentos de 1,2 a 2,0 vezes em relação ao controle, não havendo mudanças significativas na cor das uvas irradiadas. / The state of Rio Grande do Sul, Brazil, is the greatest producer of grapes in the country. Vitis labrusca cultivars constitute more than 90% of production, underscoring Isabel and Bordô varieties, featuring high concentrations of polyphenols, especially antioxidant anthocyanins used as food coloring. Since the use of the compounds in food is rather difficult due to their unstableness, microencapsulation is one of the methods to protect the compounds from adverse environmental condition. Grape pomace, the residue from the manufacture of juice and wine, has high polyphenol concentration and is mainly formed by grape skin. Current thesis aims at extracting polyphenols from the skin of Isabel and Bordô grape varieties and their micro-encapsulation by different wall materials. Research was divided into three stages. The first stage comprised the separation of phenolic compounds by water extraction in the acid medium of the skin of the Isabel grape variety. The extract was spray-dried for microparticles by means of gum arabic, β-cyclodextrin and hydroxypropyl-β-cyclodextrin as encapsulating agents at maximum 5% concentrations. Powders were assessed for total phenols, total monomer anthocyanins, flavonoids, flavanols, antioxidant activity (DPPH, CUPRAC and HRSA), color, humidity, water activity, solubility, hygroscopicity, glass transition temperature and micro-structure. As a rule, the powders featured high hygroscopicity, low glass transition temperature and particle agglomeration. Treatment with 3% of gum arabic 3% and 2% of β-cyclodextrin was the best, with the highest retention rate of flavonoids (67.2%), flavanols (51.1%), antioxidant activity, and with DDPH (55%) and CUPRAC (58.8%), lowest hygroscopicity (17.33%) and highest glass transition temperature (32.85 °C). In the second stage the acidified water phenolic extract from the Bordô grape skin was spray-dried and freeze-dried for microparticles with gum arabic, partially hydrolyzed guar gum and polydextrose, with a total 10% of wall material. Powders were assessed for total phenols, total monomer anthocyanins, antioxidant activity (DPPH, CUPRAC, HRSA), color, humidity, water activity, solubility, hygroscopicity, glass transition temperature, particle size and micro-structure. High retentions occurred, with more than 80% for total phenols and total monomer anthocyanins; and between 45 and 84% for antioxidant activity in all treatments under analysis. Atomized powders had lower humidity, water activity and particle size, greater solubility, higher glass transition temperature, and better morphological characteristics than the freeze-dried powders. The powder obtain by spray-dried with 5% of partially hydrolyzed guar gum and 5% of polydextrose was the best treatment due to greater retention of total phenols (89.0%), total monomer anthocyanins (99,5%) and antioxidant activity for DPPH (57.3%) and CUPRAC (83.2%). The third stage comprised dispersions of the extract of the Bordô grape skin with partially hydrolyzed guar gum 5% and polydextrose 5%, or rather, the best treatment among those prepared with Isabel and Bordô grapes. Dispersions were spray-dried and freeze-dried to obtain microparticles which underwent fast storage tests (relative humidity rates 75 and 90% at 35, 45 and 55 °C) and gastrointestinal digestion simulations (divided into two phases: gastric and intestinal phases). Total phenols, total monomer anthocyanins and antioxidant activity for ABTS were evaluated. Fast tests revealed that temperature had a significant effect on the decrease in phenol contents, with 82.5 - 93.5% retentions. Temperature, relative humidity and time were significant on the reduction of total monomer anthocyanin contents, with 3.9 – 42.3% retentions. Decrease in total monomer anthocyanin rates revealed a first order kinetics, whilst z and Ea rates indicated highly unstable freeze-dried powder for changes in temperature when higher temperatures are employed. On the other hand, D and t1/2 rates were very close between the two powders, revealing slight stability difference between the two at temperatures employed in current study. Thermodynamic parameters demonstrated an endothermic and non-spontaneous reaction. Antioxidant activity behaved similarly to total phenols with a final retention between 38.5 and 59.5%. In the case of gastrointestinal digestion simulation, the two powders released 80% phenols during the gastric phase and a significant increase in release during the intestinal phase in which spray-dried and freeze-dried powders had 90.6% and 94.9% release during the last hour of the experiment. A similar behavior was detected for antioxidant activity in which spray-dried and freeze-dried powders featured 50% during the gastric phase and a significant increase during the intestinal one, with 69.4% and 67.8% of antioxidant activity respectively by the spray-dried and freeze-dried powders during the last hour of the experiment. However, monomer anthocyanins had a significant 50% reduction of contents in the intestinal phase in which the spray-dried and freeze-dried powders had 39% and 39.8% release respectively during the last hour of the experiment. The methods for obtaining microparticles failed to affect the stability of the powder in fast storage tests and in gastrointestinal simulation tests. Current research also evaluated the effect of UV-C irradiation on Bordô grapes for post-harvest treatment. Two harvests in two different years were analyzed: grapes of the first harvest underwent 0, 0.5, 1, 4, 10 and 30 minutes irradiation (120 W) and stored at 22 °C, whereas grapes of the second harvest underwent UV-C irradiations (120 W) during 0, 0.5 and 4 minutes, coupled to ultrasound (40 kHz) for 5 minutes and stored at 22 °C. The former did not have any increase in bioactive compounds and antioxidant activity. Results of the latter, however, demonstrated a significant increase in total phenols, total monomer anthocyanins and antioxidant activity for grapes irradiated during 0.5 minutes with UV-C and for those irradiated with UV-C for 4 minutes plus ultrasound for 5 minutes. There was 1.2 - 2.0 times increase when compared to control, with no change in color in the irradiated grapes.
143

Extraktion av polyfenoler från pressrester av röda vindruvor / Extraction of polyphenols from red grape pomace

Haidarian, Behroz, Lidborg, Christina January 2011 (has links)
Antioxidanter är kemiska ämnen som är kapabla till att förhindra oxidation av andra molekyler. Dessa ämnen återfinns i djur- och växtriket och tycks ha en skyddande effekt på cellvävnad genom att motverka skadliga oxidativa reaktioner. Antioxidanter används bland annat industriellt som tillsater i livsmedel och andra produkter i syfte att förhindra oxidativ degradering och bibehålla näringsvärdet i livsmedel. I vindruvor återfinns höga koncentrationer av naturliga antioxidanter, främst i form av fenoliska ämnen. På grund av att vinindustrin bidrar till stora mänger avfall, främst i form av druvrester, är det önskevärt att hitta en effektiv metod för att återvinna fenoliska antioxidanter från avfallet.I detta arbete användes lösningsmedel-extraktion för att extrahera fenoliska ämnen från pressrester av röda vindruvor av varianten Tempranillo. Syftet var att uvärdera effekterna av extraktionsmetod, typ av lösningsmedel, extraktionstemperatur samt extraktionstid på fenol-innehåll och antioxidant aktivitet i extrakten. Två typer av extraktionsmetoder jämfördes; Soxhlet-extraktor och direkt-kontakt-extraktion (DCE), samt tre olika lösningsmedel; en blandning av etanol och vatten (1:1), ren etanol samt etyl acetat. Koncentrationen av fenoliskt innehåll i extrakten erhölls med hjälp av Folin-Ciocalteu's metod, och antioxidant aktivetet med FRAP (Ferric reducing ability of plasma) metoden.Utifrån erhållna data kunde det ses att extraktion med en blandning av etanol och vatten (1:1) som lösningsmedel gav högst fenolisk koncentration och antioxidant aktivitet för alla testade parametrar, medans etyl acetat gav de lägsta värdena. Soxhlet-extraktorn visade sig vara den bästa metoden då den gav högre värden i extrakten jämfört med DCE metoden. För DCE metoden kunde det ses att en extraktionstid på 2½ timmar vid 55 grader var mest optimalt då etanolbaserade lösningsmedel användes. / Program: Högskoleingenjörsutbildning i kemiteknik
144

Réactivité de polyphénols du vin sous conditions oxydantes : hémisynthèse des mongolicaïnes, et d’adduits entre polyphénols et thiols odorants / Reactivity  of  wine  polyphenols  under  oxidative  conditions : hemisynthesis of mongolicains and adducts between polyphenols and odorous thiols

Petit, Emilie 29 November 2013 (has links)
Le vin est un milieu complexe qui évolue tout au long des étapes devinification. Pour mieux appréhender ses qualités et ses défauts, de nombreuses équipesde recherche s’intéressent à la compréhension de la chimie du vin. Dans ce contexte, lesujet de ce mémoire concerne l’étude de l’évolution chimique de certaines moléculespolyphénoliques du vin sous conditions oxydantes et/ou acides, afin d’isoler et decaractériser de nouveaux composés susceptibles de se former dans le vin. Deux aspectssont examinés. Le premier concerne l’oxydation de deux flavano‐ellagitannins, lesacutissimines A et B, formées à partir d’un monomère de tannins condensés, lacatéchine, et d’un ellagitannin C‐glucosidique, la vescalagine, extraite du bois de chênepar le vin lors de l’élevage en barrique. Cette étude a permis d’isoler les mongolicaïnes Aet B et deux analogues du camelliatannin G et de mettre en évidence leur formation parun mécanisme d’autoxydation. Le deuxième aspect concerne l’évaluation desconséquences de la présence de certains polyphénols dans le vin sur les composésthiolés odorants. Leur comportement et leur réactivité chimiques sont décrits dans desmilieux différents, avec l’hémisynthèse de thio‐ellagitannins sous conditions acides, et laformation d’adduits thio‐catéchols et thio‐pyrogallols sous conditions oxydantes,transformations chimiques pouvant occasionner la perte des odeurs et arômes du vindus aux composés thiolés odorants. / The wine is a complex medium that evolves throughout the different stages ofthe wine making process. To understand both the qualities and defects of wine,numerous research team worldwide investigate the chemistry of wine. In this context,the subject of this thesis concerns the study of the chemical evolution of some winepolyphenolic molecules under oxidizing and/or acidic conditions in the aim of isolatingand characterizing new compounds likely formed in wine. Two aspects are examined.The first one is the study of the oxidation of two flavano‐ellagitannins, acutissimins Aand B, formed from a monomer of condensed tannins, catechin, and a C‐glucosidicellagitannin, vescalagin, extracted from oak wood by the wine solution during its agingin barrels. This study led to the isolation of mongolicains A and B and two analogues ofcamelliatannin G, and revealed their formation according to an autoxydationmechanism. The second aspect of this work concerns the consequences of the presencein wine of some polyphenols on wine odorous thiols. Their chemical behavior andreactivity are described in different media, with the hemisynthesis of thio‐ellagitanninsunder acidic conditions, and the formation of thio‐catechol and thio‐pyrogallol adductsunder oxidizing conditions, chemical transformations that could explain the loss ofodors and aromas due to wine odorous thiols.
145

CaracterizaÃÃo e obtenÃÃo de compostos fenÃlicos presentes no efluente do processamento da casca de coco verde. / Characterization and achievement of phenolic compounds present in the effluent from the processing of green coconut shell.

Ana Cristina de Abreu Siqueira 04 July 2012 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / The high consumption of green coconut water has generated increasing in the residue caused by improper discard of green coconut rind in Brazilian coast. To reduce this problem, Embrapa Tropical Agroindustry installed a Pilot Unit processing of green coconut rind to obtain fiber and powder, which ends up generating an effluent with high organic load, high sugar and polyphenols content and is called liquid of the rind of green coconut (LCCV). In order to reduce polyphenols and sugar content, alcoholic fermentation was carried out in the effluent, with 5 and 7.5% (w/v) of Saccharomyces cerevisiae, another fermentation with 5% (w/v) of S. cerevisiae wich was reused in subsequent fermentations and also polyphenols removal by adsorption using aluminum pillared clay. Phenolic compounds present in LCCV were characterized by nuclear magnetic resonance of hydrogen and liquid chromatography with mass spectrometry, it was possible to identify chlorogenic acid, isomers of caffeoyl shikimic acid, including 5-O-caffeoylshikimic acid, which is the major phenolic compound of LCCV and also, ferulic acid. LCCV total polyphenols levels were reduced by fermentation of 7769.1 mg/L to 3808.6 mg/L in the fermentation with 5% (w/v) yeast and 2892.4 mg/L in the fermentation 7,5% (w/v) yeast. In the fermentation with reuse of yeast, the reduction in polyphenols content ranged of 4084.7 to 5853.5 mg/L. The fermentation was efficient in reducing the polyphenols levels, in addition its efficacy to consume the sugars, glucose and fructose, present in LCCV. / O consumo de Ãgua de coco verde tem gerado um aumento nos resÃduos provocado pelo descarte inadequado da casca de coco verde no litoral brasileiro. A fim de minimizar esse problema, a Embrapa AgroindÃstria Tropical instalou uma unidade piloto de beneficiamento da casca de coco verde para obtenÃÃo de fibra e pÃ, o que acaba gerando um efluente com carga orgÃnica elevada, alto teor de aÃÃcar e de polifenÃis e à denominado de lÃquido da casca de coco verde (LCCV). A fim de se reduzir o teor de polifenÃis totais, foi realizada uma fermentaÃÃo alcoÃlica do efluente, com 5 e 7,5% (p/v) de Saccharomyces cerevisiae, com 5% (p/v) de S. cerevisiae que foi reutilizada fermentaÃÃes posteriores, alÃm da remoÃÃo por adsorÃÃo de polifenÃis do LCCV utilizando argila pilarizada de alumÃnio. Os compostos fenÃlicos presentes no LCCV foram caracterizados atravÃs de ressonÃncia magnÃtica nuclear de hidrogÃnio e cromatografia lÃquida acoplada à espectrometria de massa, onde foi possÃvel identificar o Ãcido clorogÃnico, isÃmeros do Ãcido cafeoil chiquÃmico, entre eles o Ãcido 5-O-cafeoil chiquÃmico, que à o composto fenÃlico majoritÃrio do LCCV e Ãcido ferÃlico. A fermentaÃÃo reduziu os teores de polifenÃis totais do LCCV, passando de 7769,1 mg/L a 3808,6 mg/L com a fermentaÃÃo com 5% (p/v) de levedura e para 2892,4 mg/L com a fermentaÃÃo com 7,5% (p/v) de levedura. Para a fermentaÃÃo com reutilizaÃÃo de levedura, a reduÃÃo na concentraÃÃo de polifenÃis variou de 4084,7 a 5853,5 mg/L. A fermentaÃÃo foi eficiente na reduÃÃo dos teores dos polifenÃis e no consumo dos aÃÃcares glicose e frutose presentes no LCCV.
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Perfil Fitoquímico e Capacidade Antioxidante de Extratos de Erva-mate (Ilex Paraguariensis A.st. Hill.) / Phytochemical Profile and Antioxidant Capacity of Yerba Mate Extracts (Ilex Paraguariensis A.St. Hill.)

Colpo, Ana Zilda Ceolin 16 November 2012 (has links)
Submitted by Sandro Camargo (sandro.camargo@unipampa.edu.br) on 2015-03-09T02:24:14Z No. of bitstreams: 1 116110001.pdf: 1574524 bytes, checksum: 48077bd97e3cbf3cc22e4347e94b7abf (MD5) / Made available in DSpace on 2015-03-09T02:24:14Z (GMT). No. of bitstreams: 1 116110001.pdf: 1574524 bytes, checksum: 48077bd97e3cbf3cc22e4347e94b7abf (MD5) Previous issue date: 2012-11-16 / A erva-mate, cientificamente denominada, Ilex paraguariensis St. Hil. Var. paraguariensis (Aquifoliaceae), trata-se de uma árvore que cresce naturalmente em florestas da América do Sul (na Argentina, sul do Brasil, Uruguai e Paraguai). Bebidas a base de ervas-mate denominadas “mate”, “chimarrão” ou “tererê” fazem parte dos hábitos e costumes da população local. Nos últimos anos, através da ampliação do conhecimento científico a respeito de seus efeitos na saúde, os usos da planta têm se expandido para outras partes do mundo e são descritas diversas possibilidades de aplicação. Suas ações incluem atividades antioxidante, antiinflamatória, antimutagênica, antiglicação entre outras, sendo estas diretamente relacionadas aos compostos bioativos presentes, especialmente na folha da árvore (principal parte utilizada para produção da erva-mate). Entre as substâncias conhecidas estão os polifenóis, saponinas, xantinas, minerais e vitaminas. Muitos fatores influenciam o teor desses compostos no produto final que é comercializado e por conseqüência no que é ingerido pelo consumidor. O presente estudo avaliou a composição fitoquímica e os potencias antioxidantes de extratos de ervas comercializados no Brasil, Argentina e Uruguai. Objetivando a obtenção de extratos com composição similar aos ingeridos pela população, preparou-se a bebida da forma tradicional e empregou-se uma forma de extração que mimetiza seu consumo. A partir desses extratos (mates) foram quantificados o conteúdo total de polifenóis, as concentrações das substâncias: ácido clorogênico, ácido cafeico, cafeína e teobromina e analisados os potenciais antioxidantes dos extratos. Para este fim foram utilizadas análises cromatográficas, espectrofotométricas e desenvolvidos ensaios, in vitro, que testaram a capacidade dos extratos seqüestrarem óxido nítrico e quelarem ferro. Foi possível verificar que a seqüência de extrações é um fator que influência no conteúdo extraído, visto que houveram diferenças significativas entre os primeiros e os últimos extratos. Além disso, verificou-se que a capacidade antioxidante dos extratos é expressiva e se mantêm mesmo em extratos onde a concentração de compostos apresenta decaimento significativo. No entanto, foram notadas variações relacionadas principalmente às nacionalidades das ervas. Este estudo sintetiza uma contribuição importante para futuras pesquisas, pois elucida o que é ingerido quando a bebida é consumida da forma que a população o faz, colocando a forma de extração como um importante fator, relacionado ao desfecho de seu consumo na saúde. / The yerba-mate, scientifically named, Ilex paraguariensis St. Hil. Var. paraguariensis (Aquifoliaceae), it is a tree that grows naturally in forests of South America (in Argentina, southern Brazil, Uruguay and Paraguay). Yerba mate based drinks are part of the customs and habits of the population and are called "mate", "chimarrão" or "tererê". In recent years, through the expansion of scientific knowledge about their effects in health, the plant uses has been expanded to other parts of the world and are described various possibilities of the application. Their actions include antioxidant capacity, anti-inflammatory, antimutagenic, anti-glycation and others, which are directly related to the bioactive compounds presents, especially in the leaves of the tree (the main part used for the production of yerba mate). Among the substances known are polyphenols, saponins, xanthines, vitamins and minerals. Many factors influence the content of these compounds in the end product that is marketed, and consequently in what is ingested by the consumer. The present study evaluated the phytochemical composition and the antioxidant potential of yerba-mate extracts sold in Brazil, Argentina and Uruguay. Aiming to get extracts with composition similar to the population consumes, the beverage was prepared in the traditional way and to extraction was used a method that mimics its consumption. From these extracts (mates) were quantified the total polyphenol content, the concentrations of the substances: chlorogenic acid, caffeic acid, caffeine and theobromine, and analyzed the antioxidant potential of the extracts. To this end were developed chromatographic, spectrophotometric analysis and, in vitro, carried out trials that tested the ability of the extracts to scavenger oxide nitric and to chelate iron. Was observed that the sequence of extraction is a factor that influences the extracted content, since there were significant differences between the first few and the last ones extracts. It was found that the antioxidant activity of the extracts is quite significant and remains in extracts where the concentration of compounds presents significant decline. However variations were noted, it’s related primarily to the nationalities of herbs. This study summarizes an important contribution to other research, because it clarifies what is ingested when it is drunk the way that people do it, putting the extraction as an important factor related to the outcome of their consumption on health.
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Efeito Antioxidante do Vinho Tannat Produzido em Itaqui (RS) sobre o Estresse Oxidativo em Modelo de Hiperglicemia In Vitro / Antioxidant Effect of Tannat Wine Produced in Itaqui (RS) on Oxidative Stress in Model of Hyperglycemia In Vitro

Pazzini, Camila Eliza Fernandes 16 November 2012 (has links)
Submitted by Sandro Camargo (sandro.camargo@unipampa.edu.br) on 2015-03-09T02:33:51Z No. of bitstreams: 1 116110002.pdf: 901358 bytes, checksum: edf3d6fae4ace04065873f00039b9507 (MD5) / Made available in DSpace on 2015-03-09T02:33:51Z (GMT). No. of bitstreams: 1 116110002.pdf: 901358 bytes, checksum: edf3d6fae4ace04065873f00039b9507 (MD5) Previous issue date: 2012-11-16 / A hiperglicemia leva a uma série de fenômenos bioquímicos que estão envolvidos na gênese do estresse oxidativo. O vinho é considerado um alimento antioxidante por conter uma grande quantidade de compostos fenólicos. O objetivo desse estudo foi observar o efeito antioxidante do vinho Tannat (safra 2006), produzido em Itaqui (RS), sobre o estresse oxidativo induzido por glicose ou frutose em eritrócitos in vitro. Eritrócitos foram incubados durante 24 horas a 37°C com concentrações de 5, 10, 30 e 100 mmol/L de glicose ou frutose, na presença ou ausência de diferentes volumes de vinho (0,075, 0,15 e 0,225 mL de vinho/mL de eritrócitos). Foram determinadas espécies reativas ao ácido tiobarbitúrico, consumo de glicose e fragilidade osmótica dos eritrócitos, além de polifenóis totais, antocianinas totais, ácido gálico, ácido caféico, epicatequina, resveratrol e a capacidade antioxidante (DPPH) do vinho. Os eritrócitos incubados com glicose e frutose apresentaram um aumento significativo da peroxidação lipídica quando comparados com eritrócitos incubados com 5 mmol/L de glicose ou frutose, o que foi prevenido com a adição de vinho. O vinho tinto apresentou altas concentrações de polifenóis totais, ácido gálico, ácido caféico, epicatequina e resveratrol, além de boa capacidade antioxidante. O consumo de glicose pelos eritrócitos nas concentrações de 5 e 10 mmol/L foi significativo, o que não ocorreu para os eritrócitos incubados com 30 e 100 mmol/L de glicose. O volume de 0,075 mL de vinho foi capaz de prevenir a inibição da captação de glicose pelos eritrócitos incubados com 30 e 100 mmol/L de glicose. No teste de fragilidade osmótica concentrações hipotônicas de NaCl induziram lise progressiva dos eritrócitos, que foi significativa apenas para os eritrócitos incubados com 30 e 100 mmol/L de frutose, sendo esta revertida através do tratamento dos eritrócitos com o vinho. Podemos concluir que o vinho tinto, a partir do volume mais baixo utilizado, pode diminuir a peroxidação lipídica, prevenir a inibição da captação de glicose pelos eritrócitos, além de diminuir a fragilidade osmótica de eritrócitos incubados com frutose. Este efeito antioxidante do vinho se deve, provavelmente, às altas concentrações de polifenóis encontrados e sua boa capacidade antioxidante. / Hyperglycemia leads a series of biochemical phenomena that are involved in the genesis of oxidative stress. The wine is considered an antioxidant food to contain a large amount of phenolic compounds. The aim of this study was to observe the antioxidant effect of Tannat wine (vintage 2006), produced in Itaqui (RS), on oxidative stress induced by glucose or fructose in erythrocytes in vitro. Erythrocytes were incubated for 24 hours at 37°C with concentrations of 5, 10, 30 and 100 mmol/L glucose or fructose in the presence or absence at different volumes of wine (0.075, 0.15 and 0.225 mL of red wine/mL of erythrocytes). Were determined Thiobarbituric acid reactive species, glucose consumption and osmotic fragility of erythrocytes; in addition total phenolic, anthocyanins, gallic acid, caffeic acid, epicatechin, resveratrol and the DPPH Scavenging Activity of wine. Erythrocytes incubated with glucose and fructose showed a significant increase in lipid peroxidation compared with erythrocytes incubated with 5 mmol/L glucose or fructose, which was prevented by addition of wine. The red wine presented high concentrations of total polyphenols, gallic acid, caffeic acid, epicatechin and resveratrol, further good antioxidant potential. The consumption of glucose by the erythrocytes at concentrations of 5 and 10 mmol/L was significant, this was not observed for the erythrocytes incubated with 30 and 100 mmol/L glucose. The volume of 0.075 ml of wine was able to prevent the inhibition of glucose uptake by erythrocytes incubated with 30 and 100 mmol/L glucose. In the test of osmotic fragility hypotonic concentrations of NaCl induced lysis of erythrocytes progressive, which was significant only for erythrocytes incubated with 30 and 100 mmol/L fructose, this being reversed by treating cells with wine. We conclude that red wine, from the lower volume used, can decrease lipid peroxidation, prevented the inhibition of glucose uptake and decreased osmotic fragility of erythrocytes incubated with fructose. This antioxidant effect of wine is probably due to high concentrations of polyphenols and its good antioxidant capacity.
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Avaliação do efeito fotoprotetor de compostos fenólicos sobre culturas de células da pele irradiadas por UVA e UVB / Photoprotective effect evaluation phenolic compounds on skin cell cultures irradiated with UVA and UVB

Andrea Costa Fruet 14 April 2015 (has links)
A exposição excessiva à radiação Ultravioleta (UV) resulta em manifestações clínicas à pele humana como queimaduras, fotoenvelhecimento e câncer. A radiação UVA, preferencialmente, induz à formação de espécies reativas de oxigênio, enquanto que a radiação UVB é absorvida diretamente pelo DNA. Apesar de mecanismos endógenos auxiliarem na prevenção/reparação dos danos causados pela radiação UV, quando o dano excede a capacidade de reparação celular, diversos efeitos lesivos ocorrem na pele como alterações da matriz dérmica, resposta inflamatória e desidratação do estrato córneo. O uso de compostos fenólicos com atividade antioxidante pode auxiliar na prevenção das consequências patológicas da exposição à radiação UV. O presente trabalho teve como objetivo estudar em cultura de células da pele (HaCaT -queratinócito humano imortalizado e FHPD - fibroblasto humano primário dermal) exposta às radiações UVA e UVB a atividade fotoprotetora de 3 compostos fenólicos, ácido cafeico (AC), clorogênico (ACG) e rosmarínico (AR). Inicialmente, células HaCaT e FHPD cultivadas em monocamada foram expostas às doses crescentes de radiação UVA ou UVB e, após 24 horas, foram analisadas quanto a viabilidade, marcadores de morte celular, mediadores inflamatórios, presença de aquaporina e lesões de DNA. HaCaT quando exposta às radiações UVA e UVB são conduzidas à morte por apoptose, com aumento de Caspases 3 e 9, p53 e redução de PARP. Após a exposição à radiação UVA, HaCaT responde com aumento na liberação de IL-6, TNF-α e COX-2, internalização/redução de AQP3 da membrana, redução na liberação de MMP-2 e 9, aumento na liberação de MMP-1 e na produção de ERO. Quando expostos à radiação UVB, HaCaT aumenta a liberação de IL-6 e COX-2, promove internalização/redução de AQP3 na membrana e redução na liberação de MMP-2 e 9. FHPD são menos sensíveis à exposição a ambas as radiações, mostrando redução de viabilidade com parada de ciclo apenas frente à radiação UVA. Além disto, FHPD exposto a radiação UVA responde com aumento na liberação de IL-6 e danos no DNA do tipo 8-oxo-dG. Dentre os compostos, o ACG apresentou melhor atividade fotoquimioprotetora perante ambas as radiações UVA e UVB, pois foi capaz de reverter em HaCaT a morte celular induzida por ambas as radiações e de reverter a parada de ciclo em FHPD expostos à radiação UVA. HaCaT tratado com ACG e exposto à radiação UVA responde com aumento na expressão de AQP3 e PARP, aumento na expressão gênica de AQP3, redução na expressão gênica de CDKN1A e na liberação de MMP-1, 2 e 9. Após a radiação UVB, o tratamento com ACG aumenta a expressão gênica de AQP3, reduz a expressão gênica de CDKN1A, reduz a produção de COX-2 e aumenta a liberação de MMP-2 e 9. O tratamento com o AR apresentou atividade fotoquimioprotetora frente à radiação UVA, com HaCaT respondendo a radiação com aumento na população de células viáveis, aumento na expressão de AQP3 e PARP e na expressão gênica de AQP3, redução na liberação de MMP-1 e 9 e redução na produção de COX-2. FHPD tratados com AR apresentaram aumento na população em fase G1, na expressão de p21, e redução de danos de DNA tipo 8-oxo-dG. O tratamento de HaCaT com AC foi capaz de reverter a morte celular, aumentar a expressão de p53 e aumentar a liberação de MMP-2 e 9 frente à radiação UVB e de reduzir a produção de ERO, a expressão de p21 e a liberação de MMP-1, 2 e 9 frente à radiação UVA. Para FHPD, o tratamento com AC foi capaz apenas de reduzir a formação de danos de DNA tipo 8-oxo-dG. Os resultados indicam que o modelo proposto foi capaz de discriminar a atividade fotoprotetora dos compostos frente à radiação UVA e UVB. Além disto, foi possível demonstrar que os compostos antioxidantes se comportam de maneira distinta enquanto fotoprotetores no modelo empregado. / Excessive exposure to Ultraviolet radiation (UV) results in clinical manifestations in human skin such as burns, photo-aging and cancer. UVA radiation preferentially induces formation of reactive oxygen species, while UVB radiation is absorbed directly by the DNA. Although endogenous mechanisms are able to prevent/repair cellular damages caused by UV radiation, excess cellular damage retains cells repair capacity and also results on diverse harmful effects on skin, such as, changes in the dermal matrix, inflammatory response and dehydration of the stratum corneum. The use of phenolic compounds with antioxidant activity may help preventing pathological conditions caused by UV radiation. This work aimed to study the photoprotective activity of three phenolic compounds, caffeic (CA), chlorogenic (CGA) and rosmarinic acid (RA) in human skin cells (HaCaT - immortalized human keratinocytes and HDSF - human dermal skin fibroblast) exposed to UVA and UVB radiation. Initially, HDSF and HaCaT cells were exposed to increasing doses of UVA and UVB radiation. After 24 hours of exposure, we evaluated cell viability, cell death, inflammatory mediators, aquaporin and DNA damage. Exposure to UVA and UVB radiation in HaCaT cells results on apoptotic cell death, with an increase of caspases 3 and 9, p53 and reduction of PARP. HaCaT cells when exposed to UVA radiation resulted on increased levels of IL-6, TNF-α and COX-2, internalization of the membrane AQP3, reduction of MMP-2 and MMP-9 release, increase of MMP-1 and ROS production. After UVB radiation, HaCaT cells resulted on an increase of IL-6 and COX-2 production, it also promoted internalization of membrane AQP3 and reduced release of MMP-2 and 9. HDSF were less sensitive to both radiations. Moreover, HDSF resulted in cell viability decrease and cell cycle arrest only after UVA radiation. Furthermore, HDSF when exposed to UVA radiation resulted on an increase of IL-6 production and in DNA damage (8-oxo-dG). Among the studied compounds, CGA presented better photochemiprotective activity towards UVA and UVB radiation. Also, this compound was able to reverse cell death in HaCaT after exposure to both radiations and inhibited cell cycle arrest in HDSF after UVA radiation exposure. HaCaT cells treated with CGA and exposed to UVA radiation resulted on an increase in AQP3 and PARP expression, increased in AQP3 gene expression, reduction in CDKN1A gene expression and reduction in MMP-1, 2 and 9 release. After UVB radiation, GCA treatment increases AQP3 gene expression, reduces CDKN1A gene expression, reduces COX-2 production and increase MMP-2 and 9 releases. The AR treatment showed photochemiprotective activity towards the effects of UVA radiation, with HaCaT responding with an increase on cells viability, increased in PARP and AQP3 expression and in AQP3 gene expression, decreased MMP-1 and 9 releases and reduced COX-2c production. HDSF when treated with AR showed an increase in G1 phase population, in p21 expression and reduced DNA damage-type 8-oxo-dG. HaCaT cells treated with AC reversed cell death, increased p53 expression and increased MMP-2 and 9 releases after UVB radiation and reduced ROS production, p21 expression and MMP -1, 2, 9 release after UVA radiation. HDSF treated with AC was only able to reduce the formation of 8-oxodG DNA damage. These results indicated that the proposed model was able to discriminate the photochemiprotective activity of the studied compounds against the UVA and UVB radiation. In addition, it was demonstrated that the each studied antioxidant have different photoprotective mode of action.
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Mecanismos de ação antioxidante de extratos de murici (Byrsonima crassifolia (L.) Kunth) / Mechanisms of antioxidant activity of extracts of murici (Byrsonima crassifolia (L.) Kunth)

Mariana Séfora Bezerra Sousa 23 May 2013 (has links)
Introdução: O murici (Byrsonima crassifolia (L.) Kunth) é um fruto utilizado pela população como alimento ou como agente terapêutico, mas ainda há poucos estudos sobre as suas propriedades funcionais. Assim, este trabalho objetivou caracterizar os frutos do murici quanto à composição de compostos antioxidantes e avaliar seus mecanismos de ação antioxidante in vitro. Metodologia: Os frutos do murici foram coletados na cidade de Araiozes, Maranhão, Brasil. A composição centesimal foi avaliada pelos métodos oficiais de análise e o perfil de minerais por espectrometria de emissão ótica com plasma indutivamente acoplado. Os perfis de carotenóides, tocoferóis e vitamina C foram determinados por comatografia líquida de alta eficiência. As condições ótimas para a extração de polifenóis de murici foram definidas por meio de planejamento composto central rotacional. Assim, o extrato A foi obtido usando 43,4 por cento de acetona a 28,9°C por 50,8 minutos e o extrato B com 45,2 por cento de acetona a 40°C por 52,8 minutos. Os extratos foram avaliados quanto ao perfil de compostos fenólicos por HPLC-ESI/MS e quanto aos mecanismos de ação antioxidante in vitro. Resultados: Os frutos de murici apresentaram (valor médio) 74,35 por cento de umidade, 0,94 por cento de cinzas, 0,68 por cento de proteínas, 1,82 por cento de lipídios, 4,31 por cento de carboidratos disponíveis e 17,91 por cento de fibras. Quanto ao perfil de minerais, o murici é uma boa fonte de potássio (338.58 mg 100 g 1 ), cobre (200 µg 100g ) e magnésio (35.91 mg 100 g 1 ). Os frutos apresentaram 57,41 mg/100 g vitamina C, 308,97 µg/g de luteína, 16,78 µg/g de -caroteno, 3,80 µg/g de -criptoxantina, 6,49 mg/100 g de - tocoferol, 017 mg/100 g de -tocoferol, 2,66 mg/100 g de -tocoferol e 0,33 mg/100 g de -tocoferol. A análise por HPLC-ESI/MS permitiu a identificação de 19 compostos fenólicos nos extratos de murici, sendo três dímeros de proantocianidinas, dois isômeros de catequina, ácido gálico, quercetina e seus derivados, entre outros. Os extratos de murici agiram eficientemente contra os radicais ABTS (TEAC de 158,48 µM Trolox/ g murici fresco para o extrato A e 170,17 para o extrato B), peroxil (1252,88 µM Trolox/ g extrato para o extrato A e 1332,78 para o extrato B), hidroxil (IC = 300,68 µg/mL para o extrato A e 281,33 para o extrato B), superóxido (IC 50 = 374,50 µg/mL para o extrato A e 350,92 para o extrato B). Os extratos inibiram a atividade da enzima xantina oxidase de maneira dose-dependente, porém, foram necessárias altas concentrações. No sistema Rancimat, a adição do extrato A na concentração de 2 mg/mL incrementou o tempo de indução da oxidação em 42,17 por cento , enquanto que o extrato B incrementou em 59,18 por cento . Já no sistema de cooxidação -caroteno/ácido linoleico, 150 µg/mL dos extratos inibiram cerca de 50 por cento da oxidação. Conclusão: Os frutos do murici são fontes potenciais de compostos antioxidantes, os quais atuam como scavengers de radicais livres, inibem a atividade da enzima xantina oxidase e a oxidação de lipídios / Introduction: The murici (Byrsonima crassifolia (L.) Kunth) is a fruit used by the population as food or as a therapeutic agent, but there are few studies about their functional properties. This study aimed to characterize the fruits of murici regarding the composition of antioxidant compounds and to evaluate their mechanisms of antioxidant action in vitro. Methods: The murici were obtained from Araiozes, Maranhão, Brazil. The chemical composition was assessed by official methods of analysis and profile of minerals by optical emission spectrometry with inductively coupled plasma. The analyses of vitamin C, carotenoids and tocoferols were performed by HPLC. Response surface methodology was employed to optimize the extraction of murici phenolics. The optimized conditions were 43.4 per cent acetone for 50.8 min. at 28.9°C (Extract A) and 45.2 per cent acetone for 52.8 min. at 40°C (Extract B). Phenolic compounds of the murici extracts were evaluated by HPLC-ESI/MS and the mechanisms of its antioxidant action were analyzed by in vitro methods. Results: The murici presented (average) 74.35 per cent moisture, 0.68 per cent protein, 1.82 per cent fat, 4.31 per cent carbohydrate and 17.91 per cent fiber. Concerning the profile of minerals, murici is a good source of potassium (338.58 mg 100 g ), copper (200 mg 100g -1 ) and magnesium (35.91 mg 100 g -1 ). The presence of vitamin C (57.41 mg 100g -1 ), lutein (308.97 mg g -1 1 ), -cryptoxanthin (3.80 mg g -1 ), -carotene (16.78 mg g ), -tocopherol (6.49 mg 100 g ), tocopherol (0.17 mg 100 g -1 ), -tocopherol (2.66 mg 100 g ) and tocopherol (0.33 mg 100 g -1 ) was observed in its composition. Nineteen phenolics have been identificated in murici extracts, as three dimers proanthocyanidins, two isomers of catechin, gallic acid, quercetin and their derivatives. Murici extracts acted effectively against radical ABTS (TEAC of 158.48 88 µM Trolox/g fresh murici to extract A and 170.17 to extract B), peroxyl (1252.88 µM Trolox/g extract to extract A and 1332.78 to extract B), hydroxyl (IC = 300.68 µg/mL to extract A and 281.33 to extract B) and superoxide (IC 50 = 374.50 µg/mL for the extract A and 350.92 to extract B). High concentrations of the extracts inhibited the activity of the enzyme xanthine oxidase in a dose-dependent manner. The result found by the Rancimat® method showed that the extract A at 2 mg/mL increased the oxidation induction time 42.17 per cent , while the extract B increased 59.18 per cent . Already in the -carotene/linoleate model system, 150 µg/mL of extracts inhibited the oxidation by 50 per cent . The study still showed that the extract antioxidants may be effective in blocking radical chain reactions and may also interfere with the reactions that produce the secondary products that speed up the systems oxidative process. Conclusion: The murici is potential source of antioxidant compounds, which act as scavengers of free radicals, inhibit the activity of the enzyme xanthine oxidase and lipid oxidation
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Effects of octadecaenoic acids and apple polyphenols on blood cholesterol.

January 2007 (has links)
Lam, Cheuk Kai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 148-173). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.i / ABSTRACT --- p.ii / LIST OF ABBREVIATIONS --- p.vi / TABLE OF CONTENTS --- p.x / Chapter CHAPTER 1 --- GENERAL INTRODUCTION / Chapter 1.1 --- Introduction to Cholesterol and Its Related Diseases --- p.1 / Chapter 1.1.1 --- Chemistry of cholesterol --- p.1 / Chapter 1.1.2 --- Physiological importance of cholesterol --- p.1 / Chapter 1.1.3 --- Pathological effects of cholesterol --- p.3 / Chapter 1.1.3.1 --- Mechanism of atherosclerosis --- p.3 / Chapter 1.2 --- Cholesterol Homeostasis --- p.6 / Chapter 1.2.1 --- Liver as the main organ for cholesterol metabolism --- p.6 / Chapter 1.2.2 --- Regulatory sites of cholesterol metabolism --- p.6 / Chapter 1.2.2.1 --- Regulation of cholesterol absorption by acyl coenzyme A: cholesterol acyltransferase (ACAT) --- p.6 / Chapter 1.2.2.2 --- Sterol regulatory element-binding protein 2 (SREBP-2) as a transcription factor for 3 -hydroxy-3 -methylglutaryl coenzyme A reductase (HMGR) and low-density lipoprotein receptor (LDLR) --- p.10 / Chapter 1.2.2.3 --- Roles ofLDLR --- p.11 / Chapter 1.2.2.4 --- Rate limiting role of HMGR in cholesterol de novo synthesis --- p.14 / Chapter 1.2.2.5 --- Roles of liver-X-receptor-a (LXR-a) in cholesterol catabolism --- p.16 / Chapter 1.2.2.6 --- Roles of CYP7A1 in catabolism of cholesterol into bile acids --- p.19 / Chapter 1.2.2.7 --- Roles of cholesterol ester transfer protein (CETP) in maintaining cholesterol distribution in blood --- p.22 / Chapter CHAPTER 2 --- EFFECT OF OCTADECAENOIC ACIDS ON BLOOD CHOLESTEROL IN HAMSTERS / Chapter 2.1 --- Introduction --- p.25 / Chapter 2.1.1 --- Effects of polyunsaturated fatty acids (PUFAs) on blood cholesterol --- p.25 / Chapter 2.1.2 --- Differential effects of 18-C PUFAs on lowering blood cholesterol in vivo --- p.25 / Chapter 2.1.3 --- "Structures, metabolism and conjugation of octadecaenoic acids (ODA)" --- p.26 / Chapter 2.1.4 --- Objectives --- p.26 / Chapter 2.2 --- Experiment 1 --- p.28 / Chapter 2.2.1 --- Materials and methods --- p.28 / Chapter 2.2.1.1 --- Experimental fatty acids --- p.28 / Chapter 2.2.1.1.1 --- Isolation of LN from flaxseed --- p.28 / Chapter 2.2.1.1.2 --- Isolation of CLN from tung seed --- p.28 / Chapter 2.2.1.2 --- Animals --- p.29 / Chapter 2.2.1.3 --- Diets --- p.30 / Chapter 2.2.1.4 --- Plasma lipid measurements --- p.30 / Chapter 2.2.1.5 --- Plasma CETP activity measurement --- p.30 / Chapter 2.2.1.6 --- "Measurement of liver SREBP-2, LDLR, HMGR and CYP7A1 protein abundance by Western blotting" --- p.34 / Chapter 2.2.1.7 --- "Measurement of hepatic SREBP-2, LDLR, HMGR, LXR, CYP7A1, CETP, SR-B1 and LCAT mRNA by real time PCR" --- p.35 / Chapter 2.2.1.7.1 --- Extraction of mRNA --- p.35 / Chapter 2.2.1.1.2 --- Complementary DNA synthesis --- p.36 / Chapter 2.2.1.7.3 --- Real-time polymerase chain reaction (PCR) anaylsis --- p.36 / Chapter 2.2.1.8 --- Determination of cholesterol in liver --- p.37 / Chapter 2.2.1.9 --- Determination of fecal neutral and acidic sterols --- p.38 / Chapter 2.2.1.9.1 --- Determination of fecal neutral sterols --- p.39 / Chapter 2.2.1.9.2 --- Determination of fecal acidic sterols --- p.41 / Chapter 2.2.1.10 --- Statistics --- p.43 / Chapter 2.2.2 --- Results --- p.44 / Chapter 2.2.2.1 --- Growth and food intake --- p.44 / Chapter 2.2.2.2 --- Organ weights --- p.44 / Chapter 2.2.2.3 --- "Effects of ODA on serum TC, TG and HDL-C" --- p.44 / Chapter 2.2.2.4 --- Effect of ODA on liver cholesterol --- p.48 / Chapter 2.2.2.5 --- Effect of ODA on fecal neutral sterol output --- p.48 / Chapter 2.2.2.6 --- Effect of ODA on fecal acidic sterol output --- p.48 / Chapter 2.2.2.7 --- Effect of ODA on cholesterol balance in hamsters --- p.52 / Chapter 2.2.2.8 --- Effect of ODA on plasma CETP activity --- p.52 / Chapter 2.2.2.9 --- Correlation between blood TC and liver cholesterol --- p.52 / Chapter 2.2.2.10 --- Correlation between blood HDL-C and liver cholesterol --- p.52 / Chapter 2.2.2.11 --- Correlation between blood nHDL/HDL ratio and liver cholesterol --- p.52 / Chapter 2.2.2.12 --- Effect ofODA on liver SREBP-2 immunoreactive mass --- p.58 / Chapter 2.2.2.13 --- Effect of ODA on liver LDLR immunoreactive mass --- p.58 / Chapter 2.2.2.14 --- Effect of ODA on liver HMGR immunoreactive mass --- p.58 / Chapter 2.2.2.15 --- Effect of ODA on liver LXR immunoreactive mass --- p.58 / Chapter 2.2.2.16 --- Effect of ODA on liver CYP7A1 immunoreactive mass --- p.63 / Chapter 2.2.2.17 --- Effects ofODA on hepatic CETP mRNA --- p.65 / Chapter 2.2.2.18 --- Effects of ODA on hepatic LDLR mRNA --- p.65 / Chapter 2.2.2.19 --- Effects of ODA on hepatic LXR mRNA --- p.65 / Chapter 2.2.2.20 --- Effects of ODA on hepatic CYP7A1 mRNA --- p.65 / Chapter 2.3 --- Experiment 2 --- p.70 / Chapter 2.3.1 --- Materials and Methods --- p.70 / Chapter 2.3.1.1 --- Experimental diets --- p.70 / Chapter 2.3.1.2 --- Animals --- p.70 / Chapter 2.3.1.3 --- Intestinal acyl coenzyme A: cholesterol acyltransferase (ACAT) activity measurement --- p.70 / Chapter 2.3.1.3.1 --- Preparation of intestinal microsome --- p.71 / Chapter 2.3.1.3.2 --- ACAT activity assay --- p.71 / Chapter 2.3.2 --- Results --- p.73 / Chapter 2.3.2.1 --- Growth and food intake --- p.73 / Chapter 2.3.2.2 --- Organ weights --- p.73 / Chapter 2.3.2.3 --- "Effect of ODA on serum TC, TG and HDL-C" --- p.73 / Chapter 2.3.2.4 --- Effect of ODA feeding on fecal neutral sterol content --- p.77 / Chapter 2.3.2.5 --- Effect of ODA feeding on fecal acidic sterol content --- p.77 / Chapter 2.3.2.6 --- Effect of ODA feeding on intestinal acyl coenzyme A: acyl cholesterol transferase (ACAT) activity --- p.77 / Chapter 2.4 --- Discussion --- p.81 / Chapter CHAPTER 3 --- EFFECT OF OCTADECAENOIC ACIDS ON CHOLESTEROL-REGULATING GENES IN HepG2 / Chapter 3.1 --- Introduction --- p.86 / Chapter 3.1.1 --- HepG2 as a model of cholesterol regulation --- p.86 / Chapter 3.1.2 --- Effect of polyunsaturated fatty acids (PUFAs) on cholesterol regulating genes in cultured cells --- p.87 / Chapter 3.1.3 --- Objectives --- p.89 / Chapter 3.2 --- Materials and Methods --- p.90 / Chapter 3.2.1 --- Cell culture --- p.90 / Chapter 3.2.2 --- "Measurement of SREBP-2, LDLR, HMGR and CYP7A1 protein abundance by Western blotting" --- p.92 / Chapter 3.2.3 --- "Measurement of cellular SREBP-2, LDLR, HMGR, LXR, CYP7A1 and CETP mRNA by real time PCR" --- p.93 / Chapter 3.2.4 --- Statistics --- p.93 / Chapter 3.3 --- Results --- p.95 / Chapter 3.3.1 --- Effect of ODA on HepG2 SREBP-2 immunoreactive mass --- p.95 / Chapter 3.3.2 --- Effect of ODA on HepG2 HMGR immunoreactive mass --- p.95 / Chapter 3.3.3 --- Effect of ODA on HepG2 LDLR immunoreactive mass --- p.95 / Chapter 3.3.4 --- Effect of ODA on HepG2 LXR immunoreactive mass --- p.95 / Chapter 3.3.5 --- Effect of ODA on HepG2 CYP7A1 immunoreactive mass --- p.96 / Chapter 3.3.6 --- Effect of ODA supplementation on HepG2 SREBP-2 mRNA expression --- p.102 / Chapter 3.3.7 --- Effect of ODA supplementation on HepG2 SREBP-2 mRNA expression --- p.102 / Chapter 3.3.8 --- Effect of ODA supplementation on HepG2 LDLR mRNA expression --- p.102 / Chapter 3.3.9 --- Effect of ODA supplementation on HepG2 LXR mRNA expression --- p.106 / Chapter 3.3.10 --- Effect of ODA supplementation on HepG2 CYP7A1 mRNA expression --- p.106 / Chapter 3.3.11 --- Effect of ODA supplementation on HepG2 CETP mRNA expression --- p.106 / Chapter 3.4 --- Discussion --- p.110 / Chapter CHAPTER 4 --- EFFECT OF APPLE POLYPHENOLS ON BLOOD CHOLESTEROL IN HAMSTERS / Chapter 4.1 --- Introduction --- p.114 / Chapter 4.1.1 --- Apple is a commonly consumed fruit worldwide --- p.114 / Chapter 4.1.2 --- Potential health effects of apples --- p.114 / Chapter 4.1.3 --- Abundance of polyphenols in apple --- p.115 / Chapter 4.1.4 --- Fuji variety of apple --- p.116 / Chapter 4.1.5 --- Objectives --- p.116 / Chapter 4.2 --- Materials and Methods --- p.118 / Chapter 4.2.1 --- Isolation of AP --- p.118 / Chapter 4.2.2 --- Characterization of AP extract --- p.118 / Chapter 4.2.3 --- Effect of AP on CETP activity in vitro --- p.118 / Chapter 4.2.4 --- Effect of AP on blood cholesterol in hamsters --- p.119 / Chapter 4.2.4.1 --- Animals --- p.119 / Chapter 4.2.4.2 --- Diets --- p.120 / Chapter 4.2.4.3 --- Plasma lipids measurement --- p.121 / Chapter 4.2.4.4 --- Plasma CETP activity measurement and immunoreactive mass by Western blotting --- p.123 / Chapter 4.2.4.5 --- "Measurement of liver SREBP-2, LDL-R, HMG-R and CYP7A1 protein abundance by Western blotting" --- p.124 / Chapter 4.2.4.6 --- Statistics --- p.124 / Chapter 4.3 --- Results --- p.125 / Chapter 4.3.1 --- Polyphenol content in AP --- p.125 / Chapter 4.3.2 --- Effect of AP on CETP activity in vitro --- p.125 / Chapter 4.3.3 --- Growth and food intake --- p.128 / Chapter 4.3.4 --- Organ weights --- p.128 / Chapter 4.3.5 --- Effect of AP supplementation on the plasma lipid profile of hamsters --- p.131 / Chapter 4.3.6 --- Effect of AP feeding on plasma CETP activity of the hamsters --- p.131 / Chapter 4.3.7 --- Effect of AP on plasma CETP immunoreactive mass --- p.134 / Chapter 4.3.8 --- Effect of AP on liver SREBP-2 immunoreactive mass --- p.134 / Chapter 4.3.9 --- Effect of AP on liver LDLR immunoreactive mass --- p.134 / Chapter 4.3.10 --- Effect of AP on liver HMGR immunoreactive mass --- p.134 / Chapter 4.3.11 --- Effect of AP on liver CYP7A1 immunoreactive mass --- p.134 / Chapter 4.3.12 --- Effect of AP on liver cholesterol level --- p.140 / Chapter 4.4 --- Discussion --- p.142 / Chapter CHAPTER 5 --- CONCLUSION --- p.145 / REFERENCES --- p.148

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