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Fruit Juices: Ellagic Acid Concentration and Sensory AppealKamau, Caroline M. 28 June 2007 (has links)
No description available.
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Classification et influences des polyphénols du bois de chêne sur la qualité sensorielle des vins (Application du procédé OakScan®) / Classification and influences of oak wood polyphenols on wines sensory quality (application of OakScan® process)Michel, Julien 14 December 2012 (has links)
Lors de l’élevage des vins avec le bois de chêne, plusieurs molécules d’intérêts organoleptiques comme les ellagitanins (vescalagine, castalagine, roburines A, B, C, D, E et grandinine), sont extraites. Leurs concentrations dans le bois et le vin sont très variables et leurs cinétiques d’extraction au cours de l’élevage ainsi que leurs propriétés organoleptiques dans les vins sont mal connues. Dans le but de classifier chaque douelle pour fabriquer des barriques avec des indices en polyphénols (IP) totaux significativement différents, un système proche infrarouge (NIRS), Oakscan®, a été mis en place par la tonnellerie Radoux. Notre objectif était d’étudier l’influence de ce mode de classifications des bois au niveau de la composition moléculaire et organoleptique des vins. Dans un premier temps, la classification NIRS des bois de chêne a été confirmée par quantification des concentrations en ellagitanins totaux et moléculaire par HPLC-UV-MS. Une forte variabilité des concentrations en ellagitanins des bois est observée entre 5,95 et 32,91 mg d’équivalent acide ellagique/g de bois. De plus, la classification NIRS des bois se corrèle avec les analyses chimiques (p < 0,02%). Cette nouvelle méthode permet donc de fabriquer des barriques avec un IP moyen différent (IP : 11 à 70). Dans un second temps, des vins de différentes origines et cépages sont élevés dans les barriques classifiées. La cinétique des teneurs en ellagitanins montre l’influence de la classification des bois de chêne (p < 5%). En effet, dès les premiers mois d’élevage, une augmentation en ellagitanins jusqu’à un maximum est obtenue. Plus les bois sont riches, plus le maximum de concentration en ellagitanins des vins est élevé et décalé dans le temps. Puis, une lente diminution des concentrations en ellagitanins est observée. Les influences du grain et de la chauffe des bois ont également été analysées. La solubilisation dans les vins des composés aromatiques des bois de chêne classifiés par Oakscan® montre dans plusieurs cas que les teneurs en aldéhydes furaniques et en syringol impliqués dans les perceptions du fumé/grillé sont corrélées avec la classification NIRS et également avec l’IP des bois. Ainsi, un vin élevé au contact de bois riches en polyphénols possède des concentrations en arômes fumé/grillé plus importantes. Néanmoins, l’intensité de la chauffe a un rôle prépondérant sur les concentrations de ces arômes boisés. Parallèlement, les propriétés organoleptiques des vins élevés avec du bois de chêne à 6, 12, 18 ou 24 mois et testées par un jury entrainé, montrent des différences significatives corrélées à l’IP des barriques. Les vins élevés au contact des IP les plus importants sont significativement décrits comme plus boisés, fumés/grillés et épicé au nez. En bouche, l’amertume et l’astringence sont significativement plus importantes pour les vins élevés dans les barriques possédant les plus fortes concentrations en ellagitanins. A contrario, le fruité des vins, au nez et en bouche, est généralement noté comme moins important pour les vins élevés avec des barriques à IP le plus haut.L’influence de la classification des bois, en fonction de leurs grains et de leurs IP, sur la consommation en oxygène des vins rouges a été suivie grâce à une méthode innovante et non invasive. Les résultats montrent que 96% de l’oxygène dans le vin à T0 est consommé huit jours après entonnage. Des différences significatives (p < 0,01%), entre les vitesses de consommation de l’oxygène et l’IP ou le grain des barriques, sont observées. La vitesse de consommation d’oxygène augmente en corrélation de l’IP des barriques ou de la taille du grain. Ces résultats permettent d’envisager l’utilisation de méthodes de sélection non empiriques et fiables des bois de chêne en fonction de leurs grains ou de leurs concentrations en ellagitanins ce qui permet de fabriquer des barriques classifiées à l’aide de nos résultats conférant, au vin, des propriétés organoleptiques maîtrisées. / During the wine aging with oak wood, some compounds with interesting organoleptic properties such as ellagitannins (i.e., vescalagin, castalagin, roburins A, B, C, D, E and grandinin) are extracted. The ellagitannins concentrations in oak wood and wine are highly variable and their extractions kinetic during the aging as well as their organoleptic impacts on wines are poorly known and still unclear. In order to classify each stave according to their polyphenolics index (IP) before making the barrels, an infrared system (NIRS), Oakscan®, was develop by the tonnellerie Radoux. Our aim was to study the influence of this wood classification on the wines molecular composition and organoleptic properties.In the first place, the NIRS oak staves classification has been confirmed by the determination of the total ellagitannins concentration as well as the specific levels of each ellagitannins molecule by HPLC-UV-MS. A high variability of the ellagitannins level in wood between 5.95 ± 0.30 and 32.91 ± 0.98 mg ellagic acid equivalent/g of dry wood was observed. Furthermore, the wood infrared classification is correlated with chemical analyzes (p < 0.02%) and allow the production of barrels with different IP (IP: 11, 12, 16, 21, 26, 30, 35, 36, 39, 40, 41, 50, 51, 53, 62, 67 et 70).In a second place, some wines were aged in the classified barrels. The ellagitannins levels show the oak wood classification influences (p < 5%). Indeed, the first months of aging, the ellagitannins concentration increased until a maximum was obtain . Indeed, this maximum concentration in wine aged in barrel manufactured with the wood richer in ellagitannins was higher and latter (2.30 ± 0.05 after 4 months and 11.56 ± 0.31 mg ellagic acid equivalent/L of wine after 12 months respectively for the IP 21 and IP 70 barrels). After this maximum, a slow decrease of the ellagitannins level was observed. The influences of grain and toasting were also analyzed. The aromatics compounds solubilization of classified oak wood by Oakscan® show that the furanic aldehydes levels (furfural, alcool furfurylique et 5-méthylfurfural) and the syringol involved in the smocked/toasted aromas were correlated with the NIRS classification and the wood IP. So, a wine aged in contact with wood richer in polyphenols compounds was describe as more smocked/toasted. Nevertheless, the toasting intensity (which formed these compounds by thermo-degradation of hemicelluloses and lignins) plays a major role on their concentrations. Moreover, organoleptic properties of the wines aged with oak wood (barrels, staves) at 6, 12, 18 or 24 month and tested by trained judges were significantly impacted by the IP barrels. In fact, wine with the highest ellagitannins level was significantly described with a higher woody, smoked/burned and spicy in nose. In mouth, the bitterness and the astringency were significantly higher in wine containing the highest ellagitannins level. Whereas, the wine fruity aroma, in nose and mouth, was generally descript as lower in wine aged with the barrel with the IP higher.The influences of wood classification, in relation with the grain and the IP, on the red wine oxygen consumption after being put into barrels were analyzed with a new no invasive method. The results show that 96% of the oxygen in wine at T0 was consumed after 8 days. Significant differences (p < 0.01%) between the oxygen consumption speed and the barrel IP or the grain were observed. The oxygen consumption speed increase with correlation of barrel IP or the size of grain. These results allows the utilization of method not empirical and reliable method to select oak wood regarding their grain or their ellagitannins concentration in order to be able to produce oak barrels classified by means of our results to give organoleptic properties controlled to the wine.
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Avaliação do potencial genotóxico e antigenotóxico da fração aquosa e do isolado pedunculagina da semente de Myrciaria cauliflora (Mart) O. Berg em sistemas in vivo / Evaluation of the genotoxic and antigenotoxic potential of the aqueous fraction and of the pedunculagin isolate of the Myrciaria cauliflora (Mart) O. Berg seed in vivo systemsSilva, Rangel Moreira 30 June 2016 (has links)
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Previous issue date: 2016-06-30 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Myrciaria cauliflora (Mart), commonly known as “Jabuticaba” (Brazilian Grape) occurs in all of
South America, especially in Brazil. This species presents medicinal properties and it is popularly
used to treat diarrhea and respiratory diseases. It has already been proven several biological
activities such as antioxidant, antimutagenic and anti-proliferative. The phytochemical analysis of
M. cauliflora detected the presence of several compounds, including the ellagitannin pedunculagin.
Due to the widespread use of this species for therapeutic and food purposes, this study aimed to
evaluate the genotoxic, antigenotoxic, cytotoxic and anticytotoxic actions of the aqueous fraction
(AF) and pedunculagin from M. cauliflora seed, by micronucleus (MN) test and the comet assay in
mice bone marrow cells. In order to analyze AF and pedunculagin activities prior to CP’s toxic
effects, the animals were co-, pre- and post-treated with these substances. The results showed that
AF at 24 h treatment did not show genotoxic or cytotoxic effects in the MN test and comet assay.
However, AF showed cytotoxic action, but did not show genotoxic effect at 120 h treatment in the
MN test. In the comet assay it was able to significantly reduce the frequency of DNA breaks when
compared to the negative control. In the evaluation of the antigenotoxic and anticytotoxic effects, it
was observed that in all treatments, in both assays, AF and pedunculagin showed antigenotoxic and
anticytotoxic activities, but in the post-treatment pedunculagin increased the cytotoxic effect of CP.
In general, our results indicated that AF and pedunculagin were able to protect the mice bone
marrow cells against DNA damage induced by CP in the MN test and comet assay. These findings
indicated that AF and pedunculagin could be probable candidates for the development of new
drugs. / Myrciaria cauliflora (Mart), comumente conhecida como jabuticaba, ocorre em toda América do
Sul e especialmente no Brasil. Esta espécie apresenta propriedades medicinais e é popularmente
usada para tratar diarreia e doenças respiratórias. A essa espécie já foram atribuídas várias
atividades biológicas, tais como: antioxidante, antimutagênica e antiproliferativa. A análise
fitoquímica de M. cauliflora detectou a presença de vários compostos, incluindo o elagitanino
pedunculagina. Devido ao grande uso desta espécie para fins terapêuticos e alimentícios, este
estudo teve como objetivo avaliar as ações genotóxica, antigenotóxica, citotóxica e anticitotóxica
da fração aquosa (FA) e do composto pedunculagina da semente de M. cauliflora pelo teste do
micronúcleo e ensaio do cometa em células da medula óssea de camundongos. A fim de avaliar a
atividade da FA e da pedunculagina frente aos efeitos genotóxicos da CP, os animais foram co, pré
e pós-tratados com essas substâncias. Os resultados mostraram que a FA no tempo de 24 horas não
apresentou efeitos genotóxico e citotóxico no teste do micronúcleo e no ensaio do cometa. No
tempo de 120 horas, pelo teste do micronúcleo, a FA não mostrou ação genotóxica, porém exibiu
efeito citotóxico e pelo ensaio do cometa, a frequência de quebras de DNA foi menor, quando
comparada ao controle negativo. Na avaliação dos efeitos da antigenotoxicidade e
anticitotoxicidade, em ambos os ensaios, a FA e a pedunculagina mostraram atividades
antigenotóxica e anticitotóxica, porém, no pós-tratamento, o composto pedunculagina
potencializou o efeito citotóxico da CP. De modo geral, nossos resultados indicaram que a FA e a
pedunculagina foram capazes de proteger as células da medula óssea de camundongos contra os
danos no DNA induzidos pela CP no teste do micronúcleo e no ensaio do cometa. Esses resultados
indicaram que a FA e a pedunculagina podem ser prováveis candidatos para o desenvolvimento de
novas drogas.
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Les polysaccharides et les ellagitanins du bois de chêne : influence sur la qualité sensorielle des vins / Oak wood polysaccharides and ellagitannins : the impact on sensory quality of winesLe Floch, Alexandra 16 December 2015 (has links)
Il est généralement admis que la qualité des vins et des eaux de vie dépend de leur vieillissement au contact du bois de chêne. La sélection du bois de chêne et sa maturation constituent des étapes essentielles dans la fabrication de barriques. Compte tenu des nombreux facteurs impliqués dans le choix de la matière première et dans la phase de séchage naturel du bois de chêne, il est très complexe de déterminer l’impact de la durée de séchage et l’incidence des facteurs de sélection combinés. Nous avons pu mettre en œuvre un plan d’essai qui nous a permis d’étudier l’évolution de la composition chimique du bois de chêne pour quatre stades de séchage : bois frais, 12 mois, 18 mois et 24 mois. Pour ce plan d’essai, l’échantillonnage a été réalisé en prenant en compte trois facteurs de sélection d’intérêt en tonnellerie : l’âge du bois, le type de grain et la classe d’Indice Polyphénolique mesurée par Oakscan®. En plus de la partie extractible (~10%), trois polymères constituent la majeure partie (~90%) du bois de chêne : la cellulose, les hémicelluloses et les lignines. Ces composés sont susceptibles de subir des hydrolyses ou des réactions chimiques au cours des différents processus de tonnellerie et notamment lors de la chauffe, libérant ainsi des composés aromatiques ou certains précurseurs aromatiques ayant un véritable intérêt sensoriel pour le vin vieilli en fût ou en contact avec du bois de chêne. Aucune étude n’a, à ce jour, montré un lien entre les proportions de ces composés dans le bois de chêne et l’impact au niveau chimique et organoleptique dans des vins élevés au contact de bois de chêne. Nous avons pu montrer que leurs proportions évoluent de façon significative au cours du séchage du bois de chêne et nos résultats soulignent l’incidence des différents facteurs de sélection. Respectivement, les proportions en composés extractibles, lignines, hémicelluloses et cellulose apparaissent majoritaires aux stades bois frais, 12 mois, 18 mois et 24 mois de séchage. La mise en place d’un plan d’essai sur un vin de Merlot à partir d’un deuxième échantillonnage de bois de chêne, selon les mêmes modalités que le plan d’essai sur bois, nous a permis d’évaluer l’impact du temps de séchage du bois sur la composition chimique d’un vin élevé au contact de morceaux de bois de chêne. Les résultats ont montré entre autres une baisse de près de 8% de teneur en ellagitanins moléculaires du vin entre les modalités 12 et 24 mois de séchage mais aussi des impacts sur les concentrations en composés volatiles du vin : les aldéhydes furaniques sont corrélés positivement à des temps de séchage longs (18 et 24 mois), tandis que les aldéhydes phénoliques le sont avec un temps de maturation plus court (12 mois). Nos résultats soulignent aussi l’influence des facteurs de sélection sur la composition chimique du vin. Sur le même vin de Merlot, la réalisation d’analyses sensorielles a mis en évidence des différences significatives perçues par notre panel entre les modalités de séchage 12 et 24 mois, tandis que les modalités 18 et 24 mois n’ont pas été distinguées lors de tests triangulaires. Des profils sensoriels ont également été établis pour tenter d’associer les différences perçues à un ou plusieurs descripteurs. Pour cette épreuve, les résultats soulignent la difficulté pour notre panel de dégustateurs de s’accorder sur l’existence d’une différence globale et significative entre les modalités 12 et 24 mois. Cependant, ils contribuent à expliquer les différences mises en évidence lors des tests triangulaires pour certaines modalités de séchage pour les descripteurs grillé/fumé, amertume, astringence, rondeur en bouche et perception sucrée. / It is widely accepted that alcoholic beverages quality depends on their ageing in premium quality oak wood. Oak wood selection and maturation are essential steps in the course of barrel fabrication. Given the existence of many factors involved in the choice of raw material and in natural seasoning of oak wood, it is very difficult to determine the real impact of seasoning and selection factors on oak wood composition. A sampling was done to study the evolution of oak wood chemical composition during four seasoning steps: non matured, 12 months, 18 months and 24 months. For this sampling, three selection factors were taken into account: age, grain type and the Polyphenolic Index measured by Oakscan®. Besides extractables (~10%), three polymers constitute the main part of oak wood: cellulose, hemicelluloses and lignins. These compounds may undergo hydrolysis or chemical reactions during cooperage processes, especially during heat treatment, which release some aromatic compounds or aromatic precursors having a genuine sensorial interest on wine aged in barrel or in contact with oak products. To date, no studies revealed a link between the proportions of these compounds in oak wood and the chemical and sensorial impact in wines ageing with oak wood. Our study showed that the proportions of these compounds evolved significantly during oak wood seasoning and the results highlighted the impact of selection factors. Respectively, extractables, lignins, hemicelluloses and cellulose proportions were mostly for non-matured, 12 months, 18 months and 24 seasoning months. The development of a test plan with a Merlot wine from a second oak wood sampling, using similar modalities as the previous test plan allowed the evaluation of oak wood seasoning impact on the chemical composition of a wine ageing with oak wood pieces. Results showed a lowering of 8% in ellagitannins content of wine between 12 and 24 months modalities. An impact on volatile composition in wine has also been established: furanic aldehydes were positively correlated with a long maturation time (18 and 24 months), whereas phenolic aldehydes were positively correlated with a shorter seasoning time (12 months). Our results highlighted also the impact of selection factors on wine chemical composition. Sensorial analysis on this Merlot wine led to significant differences detected by the panel between 12 and 24 seasoning modalities, but not between 18 and 24 months modalities with triangular tests. Sensorial profiles were also established to attempt to associate the differences detected to one or more descriptors. For this test, results highlighted the difficulty for the panel to make a significant difference between 12 and 24 months modalities. However they contribute to explain the differences demonstrated with triangular tests for some seasoning modalities: toasted, bitterness, astringency, roundness and sweet perception.
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Caracterização e biodisponibilidade de derivados de ácido elágico da jabuticaba (Myrciaria jaboticaba) / Characterization and bioavailability of ellagic acid derivatives from jaboticaba (Myrciaria jaboticaba).Alezandro, Marcela Roquim 19 August 2013 (has links)
O ácido elágico é um composto fenólico presente em algumas frutas e sementes. As maiores fontes da dieta humana são as frutas conhecidas como berries, a romã e as nozes. Dentre as frutas nativas brasileira, a jabuticaba apresenta teores de ácido elágico comparáveis aos das berries. Além disso, a jabuticaba representa uma boa fonte de flavonoides e destaca-se pelo sabor apreciado e pelo grande número de frutos que oferece a cada floração. Dessa forma, os objetivos deste trabalho foram: caracterizar duas espécies de jabuticaba, Sabará e Paulista (Myrciaria jaboticaba (Vell.) Berg and Myrciaria cauliflora (Mart.) O. Berg), em diferentes estádios de maturação, assim como as frações polpa, casca e semente, quanto ao teor e perfil de flavonoides, ácido elágico livre e total, elagitaninos, proantocianidinas e capacidade antioxidante in vitro. Ainda, avaliar o efeito da administração de extrato bruto e/ou frações fenólicas da jabuticaba Sabará sobre o status antioxidante e perfil bioquímico de ratos Wistar diabéticos induzidos por estreptozotocina. As frações fenólicas de jabuticaba também foram testados em modelo de prevenção de obesidade e diabetes tipo 2 induzidas por dieta hiperlipídica em camundongos C57 Black 6. Também foi avaliado o efeito de extrato bruto e frações fenólicas da jabuticaba em culturas celulares de hepatócitos FAO, macrófagos J774.1 e músculo L6. A biodisponibilidade de derivados do ácido elágico também foi estudada, tanto em modelo in vitro de fermentação quanto in vivo em ratos Wistar. Os resultados demonstraram que existem diferenças nos teores de compostos bioativos entre as espécies, e entre os estádios de maturação. A variedade Sabará destacou-se em relação à capacidade antioxidante, teor de proantocianidinas e ácido elágico total, e por ser mais cultivada e consumida pela população, foi escolhida para continuar os estudos in vivo. Em culturas celulares, o tratamento com os extratos de jabuticaba foi capaz de inibir a produção de óxido nítrico em macrófagos e hepatócitos, e aumentou a captação de glicose em células musculares. Os animais diabéticos tratados com a jabuticaba apresentaram alterações do perfil lipídico plasmático, com reversão dos altos teores de colesterol total e triacilglicerídeos. Outros efeitos como a redução da peroxidação lipídica e aumento da capacidade antioxidante plasmática também foram observados. No modelo de prevenção de obesidade e diabetes tipo 2, o tratamento com os extratos fenólicos da jabuticaba melhorou a sensibilidade à insulina e a tolerância à glicose, mesmo diante do consumo de dieta hiperlipídica e incremento ponderal dos animais. O estudo da biodisponibilidade mostrou que os derivados do ácido elágico são metabolizados especialmente pela microbiota intestinal e seus derivados foram detectados no plasma, cólon, fígado, rins, músculo e cérebro dos animais. Estes resultados demonstraram que a jabuticaba pode ser considerada uma excelente fonte de compostos bioativos e o seu consumo pode ser associado à prevenção de alterações metabólicas causadas pelo diabetes e obesidade, como a dislipidemia e a resistência à insulina. / Ellagic acid is a phenolic compound present in several fruits and nuts. Walnuts and berries are some known sources. Among the Brazilian native fruits, jaboticaba shows ellagic acid content comparable to that of berries. In addition, jaboticaba is a good source of flavonoids and stands out due to its appreciated flavor and the large number of fruits produced in each flowering. In this way, this work aimed to characterize two species of jaboticaba, Sabará and Paulista (Myrciaria jaboticaba (Vell.) Berg and Myrciaria cauliflora (Mart.) O. Berg), in different ripening stages, as well as pulp, skin and seeds, in relation to the content and composition of flavonoids, free and total ellagic acid, ellagitannins, proanthocyanidins and in vitro antioxidant capacity. Besides, evaluate the effect of raw extract and solid-phase purified phenolic fractions from Sabará jaboticaba administration on antioxidante status and biochemical profile in streptozotocin-induced diabetic Wistar rats. The jaboticaba phenolic fractions were also tested on high-fat-diet-induced obesity and type 2 diabetes in C57BL/6 mice. The effect of phenolic fractions on glucose transport in L6 muscle cells and nitric oxide production in FAO hepatocytes and J774 macrophages were also assessed. The bioavailability of polyphenols from jaboticaba were studied using in vitro and in vivo methods. The results indicated that the phenolic compounds contents are different between the two species, and among the different ripening stages. Sabará species presented the highest amounts of proanthocyanidins and total ellagic acid, and the highest antioxidant capacity. For being the most cultivated and consumed, this species was chosen for the in vivo studies. In cell cultures, the jaboticaba extracts inhibited the nitric oxide production in macrophages and hepatocytes, and increased glucose uptake in L6 muscle cells. In streptozotocin induced diabetic animals, treatment with jaboticaba led to improvement in lipid profile, reducing the levels of total cholesterol and triacylglycerol. Reduction in lipid peroxidation and increase in antioxidant capacity were also observed. In high-fat-diet induced diabetic mice, the phenolic fractions improved insulin sensitivity and glucose tolerance, even when mice become obese. The bioavailability study revealed that the ellagic acid derivatives and other jaboticaba polyphenols were metabolized, especially by the colonic microbiota, and their metabolites were detected in plasma, colon, kidneys, liver, brain, muscle, and stomach. These results demonstrated that jaboticaba may be considered an excellent source of bioactive compounds, and its consumption can be related to reduced risk of metabolic disorders caused by diabetes and obesity, such as dyslipidemia and insulin resistance.
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Caracterização e biodisponibilidade de derivados de ácido elágico da jabuticaba (Myrciaria jaboticaba) / Characterization and bioavailability of ellagic acid derivatives from jaboticaba (Myrciaria jaboticaba).Marcela Roquim Alezandro 19 August 2013 (has links)
O ácido elágico é um composto fenólico presente em algumas frutas e sementes. As maiores fontes da dieta humana são as frutas conhecidas como berries, a romã e as nozes. Dentre as frutas nativas brasileira, a jabuticaba apresenta teores de ácido elágico comparáveis aos das berries. Além disso, a jabuticaba representa uma boa fonte de flavonoides e destaca-se pelo sabor apreciado e pelo grande número de frutos que oferece a cada floração. Dessa forma, os objetivos deste trabalho foram: caracterizar duas espécies de jabuticaba, Sabará e Paulista (Myrciaria jaboticaba (Vell.) Berg and Myrciaria cauliflora (Mart.) O. Berg), em diferentes estádios de maturação, assim como as frações polpa, casca e semente, quanto ao teor e perfil de flavonoides, ácido elágico livre e total, elagitaninos, proantocianidinas e capacidade antioxidante in vitro. Ainda, avaliar o efeito da administração de extrato bruto e/ou frações fenólicas da jabuticaba Sabará sobre o status antioxidante e perfil bioquímico de ratos Wistar diabéticos induzidos por estreptozotocina. As frações fenólicas de jabuticaba também foram testados em modelo de prevenção de obesidade e diabetes tipo 2 induzidas por dieta hiperlipídica em camundongos C57 Black 6. Também foi avaliado o efeito de extrato bruto e frações fenólicas da jabuticaba em culturas celulares de hepatócitos FAO, macrófagos J774.1 e músculo L6. A biodisponibilidade de derivados do ácido elágico também foi estudada, tanto em modelo in vitro de fermentação quanto in vivo em ratos Wistar. Os resultados demonstraram que existem diferenças nos teores de compostos bioativos entre as espécies, e entre os estádios de maturação. A variedade Sabará destacou-se em relação à capacidade antioxidante, teor de proantocianidinas e ácido elágico total, e por ser mais cultivada e consumida pela população, foi escolhida para continuar os estudos in vivo. Em culturas celulares, o tratamento com os extratos de jabuticaba foi capaz de inibir a produção de óxido nítrico em macrófagos e hepatócitos, e aumentou a captação de glicose em células musculares. Os animais diabéticos tratados com a jabuticaba apresentaram alterações do perfil lipídico plasmático, com reversão dos altos teores de colesterol total e triacilglicerídeos. Outros efeitos como a redução da peroxidação lipídica e aumento da capacidade antioxidante plasmática também foram observados. No modelo de prevenção de obesidade e diabetes tipo 2, o tratamento com os extratos fenólicos da jabuticaba melhorou a sensibilidade à insulina e a tolerância à glicose, mesmo diante do consumo de dieta hiperlipídica e incremento ponderal dos animais. O estudo da biodisponibilidade mostrou que os derivados do ácido elágico são metabolizados especialmente pela microbiota intestinal e seus derivados foram detectados no plasma, cólon, fígado, rins, músculo e cérebro dos animais. Estes resultados demonstraram que a jabuticaba pode ser considerada uma excelente fonte de compostos bioativos e o seu consumo pode ser associado à prevenção de alterações metabólicas causadas pelo diabetes e obesidade, como a dislipidemia e a resistência à insulina. / Ellagic acid is a phenolic compound present in several fruits and nuts. Walnuts and berries are some known sources. Among the Brazilian native fruits, jaboticaba shows ellagic acid content comparable to that of berries. In addition, jaboticaba is a good source of flavonoids and stands out due to its appreciated flavor and the large number of fruits produced in each flowering. In this way, this work aimed to characterize two species of jaboticaba, Sabará and Paulista (Myrciaria jaboticaba (Vell.) Berg and Myrciaria cauliflora (Mart.) O. Berg), in different ripening stages, as well as pulp, skin and seeds, in relation to the content and composition of flavonoids, free and total ellagic acid, ellagitannins, proanthocyanidins and in vitro antioxidant capacity. Besides, evaluate the effect of raw extract and solid-phase purified phenolic fractions from Sabará jaboticaba administration on antioxidante status and biochemical profile in streptozotocin-induced diabetic Wistar rats. The jaboticaba phenolic fractions were also tested on high-fat-diet-induced obesity and type 2 diabetes in C57BL/6 mice. The effect of phenolic fractions on glucose transport in L6 muscle cells and nitric oxide production in FAO hepatocytes and J774 macrophages were also assessed. The bioavailability of polyphenols from jaboticaba were studied using in vitro and in vivo methods. The results indicated that the phenolic compounds contents are different between the two species, and among the different ripening stages. Sabará species presented the highest amounts of proanthocyanidins and total ellagic acid, and the highest antioxidant capacity. For being the most cultivated and consumed, this species was chosen for the in vivo studies. In cell cultures, the jaboticaba extracts inhibited the nitric oxide production in macrophages and hepatocytes, and increased glucose uptake in L6 muscle cells. In streptozotocin induced diabetic animals, treatment with jaboticaba led to improvement in lipid profile, reducing the levels of total cholesterol and triacylglycerol. Reduction in lipid peroxidation and increase in antioxidant capacity were also observed. In high-fat-diet induced diabetic mice, the phenolic fractions improved insulin sensitivity and glucose tolerance, even when mice become obese. The bioavailability study revealed that the ellagic acid derivatives and other jaboticaba polyphenols were metabolized, especially by the colonic microbiota, and their metabolites were detected in plasma, colon, kidneys, liver, brain, muscle, and stomach. These results demonstrated that jaboticaba may be considered an excellent source of bioactive compounds, and its consumption can be related to reduced risk of metabolic disorders caused by diabetes and obesity, such as dyslipidemia and insulin resistance.
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Isolamento, identificação, atividade antioxidante e variabilidade temporal de compostos fenólicos de folhas de Eucalyptus microcorys F. Muell / Isolation, identification, antioxidant activity and temporal variability of phenolic compounds in leaves of Eucalyptus microcorys F. MuellFortes , Gilmara Aparecida Corrêa 19 August 2016 (has links)
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Previous issue date: 2016-08-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The species Eucalyptus microcorys has important medicinal potential, since its leaves are rich in 1,8-cineole and hydrolysable tannins. The isolation of phenolic compounds from the leaves of this species was carried out using chromatographic methods and structural elucidation of the compounds was made by spectroscopic analysis, such as UV, IR, MS and 1H NMR and 13C, 1D and 2-D experiments. Seventeen compounds were isolated and identified, among them seven ellagitannins, four galloyl esters, four phenolic acids and two flavonoids. The acylated glycoside, 4-O-(4’,6’-di-O-galloyl -D-glucopyranosyl)-trans-p-coumaric acid, named microcoryn was first isolated in this work. Antioxidant activity of the isolated compounds was determined by two in vitro methods, free radical scavenging (DPPH) and the oxygen radical absorption capacity (ORAC). The results indicated that compounds with more phenolic hydroxyls exhibited the highest antioxidant activity, and the macrocyclic dimer oenothein B, major compound of this species, showed the highest activity. Seasonal factors and plant nutrient levels can influence the biosynthesis of secondary metabolites. This study also evaluated the temporal variability of phenolic compounds based on foliar nutrients and climatic changes in the period of two years with quarterly collections. The data were subjected to analysis of variance (ANOVA two-way); where the concentrations of oenothein B and total phenols did not show significant variations within each year, only between different years, while total tannin (astringency) varied only within the first year. Data were also analyzed by the multivariate statistical technique of time series, called primary response curve (PRC). This analysis showed that the variables that contributed most to the difference between the two years of study were copper, potassium, phosphorus, iron and magnesium as foliar nutrients, moisture and precipitation as climatic factors. Joining the results of two analyzes may suggest that variations in oenothein B levels and total phenols were influenced inversely by nutrients magnesium and iron, and directly by copper and potassium. The humidity can be an important climatic factor to the changes in total tannins, between months and years, while rainfall cannot be considered a determining factor in the variation of phenolic compounds, as it showed conflicting trends. / A espécie Eucalyptus microcorys apresenta importante potencial medicinal, pois suas folhas são ricas em 1,8-cineol e taninos hidrolisáveis. O isolamento de compostos fenólicos das folhas desta espécie foi realizado utilizando-se métodos cromatográficos e a elucidação estrutural dos compostos foi feita através de análises espectroscópicas, tais como UV, IV, EM e RMN de 1H e 13C, experimentos uni e bidimensionais. Foram isolados e identificados dezessete compostos: sete elagitaninos, quatro galoil ésteres, quatro ácidos fenólicos e dois flavonoides, sendo que o ácido trans-p-cumárico-4-O-(4’,6’-di-O-galoil-β-D-glicopiranosil), chamado de microcoryna, foi isolado pela primeira vez neste trabalho. A atividade antioxidante dos compostos isolados foi determinada através de dois métodos in vitro, o sequestro de radicais livres (DPPH) e a capacidade de absorção do radical oxigênio (ORAC). Os resultados indicaram que compostos com maior número de hidroxilas fenólicas exibiram as maiores atividades antioxidantes, sendo que o dímero macrocíclico oenoteina B, composto majoritário desta espécie, apresentou a maior atividade. A biossíntese de metabólitos secundários pode ser influenciada por fatores sazonais e níveis nutricionais da planta. Neste estudo, também foi avaliada a variabilidade temporal de compostos fenólicos em função dos nutrientes foliares e variações climáticas no período de dois anos, com coletas quadrimestrais. Os dados obtidos foram submetidos a análise de variância (ANOVA two-way), onde observou-se que as concentrações de oenoteina B e fenóis totais não apresentaram variações significativas dentro de cada ano, somente entre os diferentes anos, enquanto taninos totais (adstringência) variou apenas no primeiro ano. Os dados também foram analisados pela técnica estatística multivariada de séries temporais, denominada curva de resposta principal (PRC). Esta análise mostrou que as variáveis que mais contribuíram para a diferenciação entre os dois anos de estudo foram: cobre, potássio, fósforo, ferro e magnésio como nutrientes foliares e umidade e precipitação como fatores climáticos. Unindo-se os resultados das duas análises pode-se sugerir que as variações nos teores de oenoteina B e fenóis totais foram influenciadas inversamente pelos nutrientes magnésio e ferro e diretamente por cobre e potássio. A umidade do ar pode ser um fator climático importante para a variação de taninos totais entre meses e anos, enquanto a precipitação pluviométrica não pode ser considerada como um fator determinante na variação dos compostos fenólicos, pois mostrou tendências conflitantes.
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Compostos bioativos de cultivares brasileiras de morango (Fragaria x ananassa Duch.): caracterização e estudo da biodisponibilidade dos derivados de ácido elágico / Bioactive compounds from Brazilian strawberry cultivars (Fragaria x ananassa Duch.): Characterization and bioavailability of ellagic acid derivativesPinto, Marcia da Silva 25 November 2008 (has links)
O morango representa boa fonte de vitamina C, flavonóides e derivados de ácido elágico e tem ampla aceitação pela população brasileira. Os objetivos deste trabalho foram: caracterizar diferentes cultivares quanto aos teores de compostos bioativos, otimizar a metodologia para quantificação do conteúdo de ácido elágico total, purificar e caracterizar estruturalmente os elagitaninos, avaliar sua potencial atividade antiproliferativa, anti-diabetes tipo 2 e anti-hipertensão, estudar a biodisponibilidade desses compostos in vivo. Os resultados demonstraram que existem diferenças significativas nos teores de compostos bioativos entre as cultivares. As melhores condições para determinação dos teores de ácido elágico total foram: extração em acetona 80% e posterior hidrólise com ácido trifluoracético (TFA) 2N a 120 °C por 60 minutos. A precipitação com acetato de itérbio foi o método mais eficiente para a purificação dos elagitaninos. Após administração por gavagem a ratos de um purificado de elagitaninos, nenhum composto foi detectado no plasma e tecidos analisados. / Strawberries are a good source of vitamin C, flavonoids and ellagic acid derivatives and are consumed in Brazil in large quantities. The objectives of the present work were: characterization of different cultivars with respect to the content of bioactive compounds, optimization of the method for quantification of total ellagic acid content, purification and structural identification of ellagitannins, evaluation of their antiproliferative, anti-type 2 diabetes and anti-hypertension potentials, investigation of their in vivo bioavailability. The results indicated that there were significant differences in bioactive compounds among the strawberry cultivars. The best conditions for the determination of the total ellagic acid content in strawberries were extraction with 80% acetone, and hydrolysis using 2N TFA at 120 °C for 60 minutes. The precipitation method using ytterbium acetate was the most efficient in purifying the ellagitannins. After administration of purified ellagitannins to rats by gavage, no compound was detected in plasma or tissue samples analyzed.
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Compostos bioativos de cultivares brasileiras de morango (Fragaria x ananassa Duch.): caracterização e estudo da biodisponibilidade dos derivados de ácido elágico / Bioactive compounds from Brazilian strawberry cultivars (Fragaria x ananassa Duch.): Characterization and bioavailability of ellagic acid derivativesMarcia da Silva Pinto 25 November 2008 (has links)
O morango representa boa fonte de vitamina C, flavonóides e derivados de ácido elágico e tem ampla aceitação pela população brasileira. Os objetivos deste trabalho foram: caracterizar diferentes cultivares quanto aos teores de compostos bioativos, otimizar a metodologia para quantificação do conteúdo de ácido elágico total, purificar e caracterizar estruturalmente os elagitaninos, avaliar sua potencial atividade antiproliferativa, anti-diabetes tipo 2 e anti-hipertensão, estudar a biodisponibilidade desses compostos in vivo. Os resultados demonstraram que existem diferenças significativas nos teores de compostos bioativos entre as cultivares. As melhores condições para determinação dos teores de ácido elágico total foram: extração em acetona 80% e posterior hidrólise com ácido trifluoracético (TFA) 2N a 120 °C por 60 minutos. A precipitação com acetato de itérbio foi o método mais eficiente para a purificação dos elagitaninos. Após administração por gavagem a ratos de um purificado de elagitaninos, nenhum composto foi detectado no plasma e tecidos analisados. / Strawberries are a good source of vitamin C, flavonoids and ellagic acid derivatives and are consumed in Brazil in large quantities. The objectives of the present work were: characterization of different cultivars with respect to the content of bioactive compounds, optimization of the method for quantification of total ellagic acid content, purification and structural identification of ellagitannins, evaluation of their antiproliferative, anti-type 2 diabetes and anti-hypertension potentials, investigation of their in vivo bioavailability. The results indicated that there were significant differences in bioactive compounds among the strawberry cultivars. The best conditions for the determination of the total ellagic acid content in strawberries were extraction with 80% acetone, and hydrolysis using 2N TFA at 120 °C for 60 minutes. The precipitation method using ytterbium acetate was the most efficient in purifying the ellagitannins. After administration of purified ellagitannins to rats by gavage, no compound was detected in plasma or tissue samples analyzed.
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