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Research was conducted to investigate the effect of phenolic compounds derived from inherently rich antioxidant grape extracts (GE) on α-glucosidase inhibitory activity in vitro and in vivo blood glucose control, oxidative stress, and inflammation associated with obesity-induced type 2 diabetes. Because intestinal α-glucosidase plays a key role in the digestion and absorption of complex carbohydrates, the inhibition of this enzyme is a metabolic target for managing diabetes by improving post-prandial blood glucose control. Initially, red Norton wine grape (Vitis aestivalis) and pomace extracts were evaluated and determined to have notable phenolic content and antioxidant properties. Next, grape skin (GSE) and pomace extract (GPE) were tested and both had in vitro yeast and mammalian α-glucosidase inhibitory activity. The GSE was 32-times more potent at inhibiting yeast α-glucosidase than acarbose, a commercial oral hypoglycemic agent. From HPLC and LC-MS analysis, three phenolics from the GSE (resveratrol, ellagic acid, and catechin) were identified as active inhibitory compounds. The acute administration of GPE (400 mg/kg bw) to mice reduced postprandial blood glucose level by 35% following an oral glucose tolerance test compared to the control. The daily supplementation (250 mg/kg bw) of GSE and GPE for 12-weeks to mice affected fasting blood glucose levels, oxidative stress, and inflammatory biomarkers associated with obesity and type 2 diabetes. At the end of the study, the GSE group gained significantly (P < 0.05) more weight (24.6 g) than the control, high fat, or GPE groups (11.2, 20.2, 19.6 g, respectively). Both GSE and GPE groups had lower fasting blood glucose levels (119.3 and 134.2 mg/dL, respectively) compared to the high fat group (144.6 mg/dL). The 12-week supplementation of GSE was associated with a higher plasma oxygen radical absorbance capacity (ORAC), lower liver lipid peroxidation as measure by TBARS, and lower levels of inflammation as measured by plasma C-reactive protein compared to the high fat group. In conclusion, our collective observations from these studies provide insight into the potential effects of antioxidant rich grape extracts on diabetes-related biomarkers through a dual mechanism of antioxidant protection and specific inhibition of intestinal α-glucosidases. / Ph. D.

Le règne végétal est une ressource renouvelable d'une large gamme de métabolites secondaires biologiquement actifs. Ces travaux de thèse proposent une stratégie multidisciplinaire d'évaluation du potentiel de composés phénoliques antimicrobiens d'origine végétale pour la conservation des aliments. Un criblage de l'activité antimicrobienne in vitro vis-à-vis de 8 souches de la flore pathogène et d'altération des aliments d'une centaine de molécules pures et une soixantaine d'extraits végétaux a d'abord permis de sélectionner les plus actifs. Différents mécanismes d'action vis-à-vis de S. aureus ont pu être mis en évidence par cytométrie de flux couplée à l'utilisation de marqueurs de l'état physiologique des bactéries pour quelques uns des composés actifs sélectionnés. En vue d'une application à de la viande bovine, l'activité antibactérienne des composés phénoliques ou extraits végétaux les plus actifs a été réévaluée dans des milieux de culture plus complexes mimant leur teneur en protéines et en matières grasses. Les résultats de ce criblage et un suivi microbiologique de viande hachée de bœuf avec 1% (m/m) d'extrait ajouté ont permis d'observer que les pertes d'activité antibactérienne observées étaient notamment corrélées aux interactions des composés phénoliques avec les protéines ou les matières grasses. L'incorporation des composés phénoliques ou extraits végétaux dans des matériaux d'emballage en contact alimentaire a constitué la seconde voie de mise en œuvre envisagée. Des films plastiques conservant une activité antibactérienne ont ainsi pu être élaborés par voie fondue / The plant kingdom is a renewable resource of a wide range of biologically active secondary metabolites. This thesis proposes a multidisciplinary strategy for evaluating the potential of plant-derived antimicrobial phenolic compounds for food preservation. A screening of the antimicrobial activity in vitro against 8 strains of foodborne pathogenic and spoilage microorganisms of a hundred pure molecules and about sixty plant extracts allowed to select the most active. Different mechanisms of action with respect to S. aureus could be demonstrated by flow cytometry coupled with the use of probes of the physiological state of the bacteria for some of the selected active compounds. For application to beef, the antibacterial activity of the most active phenolic compounds or plant extracts has been re-evaluated in more complex culture media mimicking their protein and fat content. The results of this screening and a microbiological monitoring of minced beef with 1% (m / m) of added extract made it possible to observe that the observed losses of antibacterial activity were in particular correlated with the interactions of the phenolic compounds with the proteins or fat. Incorporation of phenolic compounds or plant extracts into packaging materials in contact with food constituted was the second proposed route of implementation. Plastic films that retain antibacterial activity have thus been able to be prepared by melting

Thesis (MScAgric)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Phenolic compounds are important quality indicators of a red wine, as they can contribute to the colour of a young red wine, colour stability during ageing as well as astringency, bitterness, body and overall mouthfeel properties. Wine composition is commonly influenced by winemaking and viticultural practices. In South Africa it often happens that vines are excessively vigorous, resulting in canopies that are too dense, which in turn could have a negative effect on the quantity and quality of the grapes produced. Viticultural practices such as judicious canopy management and irrigation are designed to control vine vigour and yield, thus improving fruit ripening and colour development. Artificial shading and water deficit have been reported to have an influence on the sensory properties of red wine as well as on the flavonoid composition. These effects are dependent on a number of factors, however, including the season, cultivar, light intensity, and the extent and timing of water deficit. There is limited research on the possible interactive effects of grapevine water deficits and canopy manipulation on grape and wine flavonoid composition in Shiraz, as well as the relationships between berry and wine composition. We thus investigated the effect of canopy reduction in combination with water deficit on the phenolic and colour composition of Shiraz grapes at different levels of ripeness, and in their corresponding wines after alcoholic and malolactic fermentation as well as after six months’ ageing. This study found that it is possible to improve the phenolic composition of grapes and wine by shoot removal, and some of the tendencies in the wines were also observed after the ageing period. If the shoot removal is not performed at a very early stage, sunburn damage can occur and this will result in berries with a lower mass and volume at harvest due to excessive exposure without the berry having adapted to the imposed conditions. Harvesting at different ripeness levels also affected the chemical and phenolic composition of the grapes and resulting wines. The water deficit effect on most phenolic parameters measured in the grapes and wine was not as prominent as that of the canopy manipulation treatment. This study improved our understanding of how an improvement in the canopy microclimate of Shiraz could be reflected in the phenolic composition of wines, along with a potentially important effect of harvesting date. On this basis it may be possible to attain a specific wine style. Harvesting at a ripe stage, for example, could result in the production of wines with higher colour density and astringency, while unripe grapes could result in wines with higher levels of perceivable fresh berry attributes. In particular, canopy reduction could increase the astringency and body of wines made from grapes subjected to water deficit. / AFRIKAANSE OPSOMMING: Fenoliese verbindings is belangrike kwaliteitsparameters van rooiwyn, aangesien dit kan bydra tot die kleur van ‘n rooiwyn, kleurstabiliteit tydens veroudering sowel as frankheid, bitterigheid en mondgevoel. ‘n Wyn se fenoliese samestelling word algemeen bepaal deur wynmaak- en wingerdkundige praktyke. In Suid-Afrika gebeur dit gereeld dat wingerde uitermatig groeikragtig is, wat lei tot te digte lower wat sodoende ‘n negatiewe effek op kwantiteit en kwaliteit van die druiwe wat geproduseer word, het. Wingerdkundige praktyke soos oordeelkundige lowerbestuur en besproeiing is ontwerp om wingerdstokke se groeikrag en opbrengs te beheer, en sodoende vrugrypwording en kleurontwikkeling te verbeter. Kunsmatige beskaduwing en waterstres is gerapporteer om ‘n invloed te hê op die sensoriese eienskappe van rooiwyn sowel as op die flavonoïedsamestelling. Hierdie effekte is egter afhanklik van ‘n verskeidenheid faktore, insluitende die seisoen, kultivar, ligintensiteit en die mate en tyd van waterstres toegepas. Daar is beperkte navorsing op die moontlike interaktiewe effekte van waterstres en lowermanipulasie op die druif en wyn flavonoïedsamestelling in Shiraz, sowel as die verhoudings tussen druif en wyn samestelling. Ons het dus die effekte van lowerbestuur in kombinasie met waterstres op die fenoliese en kleursamestelling van Shiraz druiwe by verskillende rypheidsvlakke ondersoek, asook in hul ooreenstemmende wyne na alkoholieseen appelmelksuurfermentasie sowel as na ses maande veroudering. Hierdie studie het gevind dat dit moontlik is om die fenoliese samestelling van druiwe en wyn deur lootverwydering te verbeter, en sommige van die tendense is ook waargeneem in die wyn na die verouderingsperiode. Indien lootverwydering nie toegepas word by ‘n baie vroeë stadium nie, kan sonbrand voorkom en dit kan lei tot korrels met ‘n laer massa en volume by oes as gevolg van oormatige blootstelling sonder dat die korrel aangepas het by die spesifieke kondisies. Oes by verskillende rypheidsvlakke affekteer ook die chemiese en fenoliese samestelling van die druiwe en ooreenstemmende wyne. Die waterstreseffek op meeste van die fenoliese parameters gemeet in druiwe en wyn was nie so prominent soos dié van die lowermanipulasie behandeling nie. Hierdie studie het ons begrip verbeter van hoe ‘n verbetering van die lower mikroklimaat van Shiraz gereflekteer kan word op die fenoliese samestelling van die wyn, saam met ‘n potensiële belangrike effek van oesdatum. Op grond van hierdie basis is dit dus moontlik om ‘n spesifieke wynstyl te verkry. Oes by ‘n ryp stadium, byvoorbeeld, kan die produksie van wyn met ‘n hoër kleurdigtheid en frankheid tot gevolg hê, terwyl onryp druiwe wyne met hoër vlakke van waarneembare vars bessiekenmerke tot gevolg kan hê. Verlaging van lowerdigtheid kan veral die frankheid en mondgevoel van wyne gemaak van druiwe blootgestel aan waterstres, verbeter.

A própolis é uma substância resinosa coletada pelas abelhas de diversas partes das plantas, como brotos, botões florais e exudados resinosos, conhecida por do ácido cinâmico e ácido benzócio, foram ainda encontrados o ácido pimárico, várias atividades biológicas como antimicrobiana, anti-inflamatória, antiproliferativa e antioxidante. Sua composição química depende de vários fatores, como a localização geográfica, vegetação e clima. A própolis brasileira com certificação de produto orgânico, proveniente do sul do Brasil, foi coletada e avaliada em diferentes estações do ano. Essa própolis é produzida em florestas nativas e áreas de reflorestamento, locais livres de contaminação por insumos agrícolas, metais pesados e poluição industrial. O objetivo deste trabalho foi avaliar a composição química e atividade antioxidante, considerando a variação sazonal das estações de verão, outono e primavera. Foram coletadas ao todo 78 amostras provenientes de 14 apiários distintos. O teor de compostos fenólicos totais e flavonoides foram feitos por métodos colorimétricos, a atividade antioxidante foi avaliada pelos métodos de sequestro dos radicais livres DPPH&bull;, ABTS+, sendo a capacidade antioxidante contra os radicais peroxila, determinado pelo método ORAC. O perfil químico do extrato de etanólico da própolis (EEPO) foi avaliado por cromatografia de camada delgada em fase reversa (CCDAE-FR), varredura no ultravioleta-visível (UV-vis) e cromatografia gasosa acoplada com espectrometria de massas (CGEM). A composição de voláteis foi analisada por CG-EM. Os teores de flavonoides variaram de não detectado até 4,76 mg.g-1 e de 6,80 a 72,55 mg.g-1 para fenólicos totais. Em relação à atividade antioxidante, a variação encontrada foi de 1,01 a 384,60 mg Trolox.g-1 para ABTS+, de 4,50 a 148,10 &micro;mol Trolox.g-1 para DPPH&bull; e de 0,20 a 1,25 &micro;mol Trolox.g-1 de amostra para o ORAC. Em relação às estações, o verão apresentou maior teor de flavonoides (p=6%) e o outono, maior teor de DPPH&bull; (p=7%). Com base no perfil químico pela técnica de CCDAE, foi possível classificar as 78 amostras em sete variantes distintas. Dentre os compostos presentes e derivados dos ácidos cinâmico e benzóico, analisados pela técnica CG/MS, identificou-se os compostos ácido pimárico, norolean-12 ene, alfa bisabolol e metil comate A. Também foram identificados oito compostos voláteis em grande quantidade como &alpha;-pineno (54,77%), &beta;- pineno (14,83%), &alpha;-limoneno (3,78%), &beta;- mirceno (9,29%), ?-candineno (2,11%), &gamma; -muroleno (1,86%), &beta;-felandreno (4,79%) e &alpha;-selineno (8,40%). Uma correlação estatística foi encontrada entre o teor de fenólicos totais e o método DPPH&bull;, p=0,78, diferentemente do teor de flavonoides que não apresentou correlação com a atividade antioxidante. Os resultados obtidos demonstraram que a própolis orgânica possui atividade antioxidante, embora apresente baixos teores de flavonoides. Não existe correlação entre os flavonoides e atividade antioxidante. Os compostos fenólicos e a atividade antioxidante foram influenciados pela sazonalidade, sendo o outono, a estação que apresentou teores maiores de fenólicos e atividade antioxidante. / Propolis is a resinous substance collected from plant buds, flowers, and exudates by Apis mellifera bees widely known for its biological activities such as antiviral, antimicrobial, anti-inflammatory, antiproliferative and antioxidant activities. Its chemical composition depends on many factors as geographic location, vegetation, and climate. A certified Brazilian propolis, originated from South Brazil, was collected and evaluated in different seasons. This kind of propolis is produced in native forest and in reforestation areas, where contamination derived from agricultural inputs, heavy metals, and factory fumes is found. Hence, the aim of this work was to evaluate the chemical composition and the antioxidant activity during seasonal variation in summer, autumn and spring. Seventy-eight samples were collected from 14 different apiaries. The phenolic compound content and flavonoids were performed by colorimetric methods. The antioxidant activity was evaluated by free radical scavenging methods such as DPPH&bull; and ABTS+. The antioxidant capacity against peroxil radicals was assessed by ORAC method. The chemical profiles of the organic propolis ethanolic extracts were evaluated by reversed-phase thin-layer chromatography (RP-TLC), ultraviolet (UV) scanning, and gas chromatography-mass spectrometry (GC-MS). Flavonoid content varied from non - detected to 4.76 mg. g-1 and 6.80 to 72.55 mg.g-1 for phenolics. The antioxidant activity varied from 1.01 to 384.60 mg Trolox.g-1 for ABTS+ and 4.50 to 148.10 &micro;mol Trolox.g-1 for DPPH. Considering the seasonal variation, summer presented the highest compound content for flavonoids (p=6%), meanwhile autumn presented the highest compound content for DPPH&bull; (p=7%). Thus, considering the chemical profile presented by RP-TLC, seven different variances of propolis were classified. Compounds such as pimaric acid, norolean-12-ene, alpha bisabolol, and methyl commate A were found by GC-MS technique on these seven variances. Eight volatile compounds were also identified as follow: &alpha;-pinene (54,77%), &beta;- pinene (14,83%), &alpha;-limonene (3,78%), &beta;-myrcene (9,29%), .-candinene (2,11%), &gamma; - muurolene (1,86%), &beta;-phellandrene (4,79%), and &alpha;-selinene (8,40%). In conclusion, the results demonstrated that autumn showed higher antioxidant activity by DPPH&bull; method than those produced in other seasons. A statistical correlation was found between phenolic compound and DPPH&bull;, p=0.78, differing from the flavonoid content which did not demonstrate a correlation with antioxidant activity. The results obtained showed that organic propolis presents antioxidant activity, although its flavonoid content is extremely low. On extent, there was no correlation between flavonoid content and antioxidant activity. Moreover, the seasonal variation showed its influence on phenolic compounds as well as on antioxidant activity, in which autumn presented the highest phenolic content and antioxidant activity.

INTRODUÇÃO: A erva-mate (Ilex paraguarienis), uma planta nativa e consumida em grande parte da América do Sul, apresenta diversos compostos bioativos que já demonstraram importante atividade antioxidante in vitro e in vivo. O chá mate é um produto desta planta cujas propriedades antioxidantes ainda não foram avaliadas em ensaios com humanos. OBJETIVO: Este projeto visa avaliar o potencial antioxidante do chá mate in vivo e ex vivo sobre o plasma e LDL de humanos após a ingestão de chá-mate. MÉTODOS: Indivíduos em jejum (n=20) tiveram seu sangue coletado em três momentos: antes, após uma hora e depois de 1 semana (7 dias) da ingestão diária de chá-mate. O plasma e a LDL obtidos nos três momentos foram submetidos à oxidação por três mecanismos diferentes [Cobre (Cu+2), lipoxigenase e peroxinitrito (SIN-1)] e em seguida foram medidos os produtos de peroxidação lipídica formados: a concentração de TBARs (substâncias reativas ao ácido tiobarbitúrico) e a formação de dienos conjugados empregando-se métodos espectrofotométricos. Também foram determinados o perfil antioxidante total do plasma (TAS), avaliação da lipoperoxidação plasmática basal (TBARs), avaliação da fragmentação da Apolipoproteína B após oxidação da LDL, por eletroforese em gel com SDS-PAGE e os níveis de expressão, por meio de análise de PCR real time, de alguns genes relacionados à produção de enzimas antioxidantes. Teste t de Student pareado foi utilizado para verificar se houve diferença estatisticamente significante entre os resultados das diversas análises antes e após o consumo do chá. RESULTADOS: Os resultados obtidos pela maioria dos ensaios realizados demonstraram que o consumo de chá mate aumentou a resistência à oxidação, a capacidade antioxidante plasmática e a expressão de genes relacionados à produção de enzimas antioxidantes. CONCLUSÃO: Esses resultados sugerem que o consumo de chá mate por período curto pode atuar como antioxidante por múltiplos mecanismos e portanto pode contribuir para diminuição do risco de desenvolvimento de doenças crônicas relacionadas a processos oxidativo. / Yerba Mate (Ilex paraguariensis) is a native and widely consumed South American plant. It contains high concentrations of bioactive compounds that respond for its high antioxidant activity in vitro and in vivo. This activity has not been demonstrated yet in humans for the mate tea, a product derived from Yerba Mate. OBJECTIVE: The aim of this study was to evaluate the antioxidant activity of maté tea in vivo and ex vivo on plasma and LDL human after ingestion of mate tea infusion. METHODS: Fasting peripheral venous blood samples of twenty healthy women (n=20) were taken in three different times: before drinking the tea, one hour later and after one week of daily consumption (7 days) of mate tea. The plasma and isolated LDL were oxidated with 3 different systems [copper (CuSO4), lipoxygenase and peroxynitrite (SIN-1)]. Next, the peroxidation products evaluated were: concentration of malonaldeyde (TBA) and conjugated dienes (lag time), using spectrophotometric methods. We also measured the plasma total antioxidant status (TAS), serum levels of malondialdehyde (MDA) as thiobarbituric substances (TBARS), fragmentation of apo B using SDS-PAGE and the level of antioxidant enzyme gene expression by PCR real time. Paired t student test was used to analyze the results before and after ingestion of mate tea. RESULTS: The results obtained by most of the tests showed that mate tea ingestion increased the plasma and LDL resistance by ex vivo oxidation, the plasma antioxidant capacity and the level of antioxidant enzyme gene expression. CONCLUSION: This study suggests that regular consumption of mate tea can act as an antioxidant by multiple mechanisms and thus may contribute decrease the risk of developing chronic diseases related to oxidative processes.

A avaliação da atividade antioxidante de compostos fenólicos em vegetais tem sido estudada como alternativa ao uso de antioxidantes sintéticos como butil hidroxi tolueno (BHT). No presente trabalho foi avaliada a capacidade antioxidante in vitro dos extratos (etéreo, etanólico e aquoso) e frações de ácidos fenólicos (livres, ésteres de ácidos fenólicos solúveis e ácidos fenólicos insolúveis ligados) do café in natura e torrado em diferentes condições de tempo (10 e 20 min) e temperatura (140ºC, 160ºC e 180ºC). As análises in vitro foram realizadas através do sistema &#946;-caroteno e ácido linoléico (que indica a inibição da oxidação em meio emulsionado) e pelo método do Rancimat (que indica a inibição da oxidação em meio lipídico). Em ambos os métodos alguns extratos e todas as frações de ácidos fenólicos apresentaram atividade antioxidante igual ou superior ao BHT nas mesmas concentrações. Independente das condições de torrefação aplicadas, o extrato aquoso apresentou a maior atividade antioxidante em função do maior conteúdo de fenólicos. Os fatores cinéticos obtidos demonstraram também resultados maiores que o BHT. O perfil de ácidos fenólicos das frações foi caracterizado por cromatografia gasosa sendo identificados os seguintes ácidos fenólicos: salicílico, ferúlico, caféico, sinápico, clorogênico, quínico, p-cumárico, gentísico e protocatequínico. Foi realizada a avaliação sensorial da infusão de café não havendo diferença estatística entre as amostras mais torradas cujas torras estão próximas das amostras comerciais (p< 0,05). Com base nesses dados a amostra torrada a 180ºC/10 min foi utilizada na avaliação do potencial antioxidante in vivo. Para tanto, ratos Wistar foram suplementados por 30 dias com diferentes doses do extrato aquoso de café torrado (180ºC/10 min). As doses ministradas foram eficientes para evitar a oxidação dos tecidos plasmático, hepático, cerebral e cardíaco quando avaliados pelo método de TBARS (substâncias reativas ao ácido tiobarbitúrico) sendo observado efeito dose resposta em todos os tecidos exceto no cardíaco (p< 0,05). O perfil lipídico do plasma dos animais suplementados em relação ao grupo controle indicou também que o extrato aquoso de café foi eficiente para inibir a oxidação dos ácidos graxos poliinsaturados (p< 0,05). Os dados aqui apresentados sugerem o uso potencial do extrato aquoso de café como antioxidante tanto como aditivo quanto o seu consumo como bebida desde que o extrato aquoso apresentou a maior atividade antioxidante. / Evaluation of antioxidant activity of plant phenolic compounds has been studied as an alternative to the use of synthetic antioxidants, such as butil-hydroxy -toluene (BHT). In this paper we evaluated the in vitro antioxidant capacity of coffee extracts (ether, ethanol and aqueous) and fractions ( free, bound and unbound) roasted for different periods of time ( 0 and 20 min) and at varying temperatures (140&#186;C, 160&#186;C and 180&#186;C). In vitro analyses were made both by the &#946;-carotene and linoleic acid (that indicates oxidation inhibition in an emulsion) as well as by the Rancimat method (that indicates oxidation inhibition in lipid medium). All extracts and fractions presented antioxidant activity equal to or higher than BHT at the same concentrations. Aqueous extract had a higher antioxidant activity due to its higher phenolic content. Kinetic factors obtained were also higher than those of BHT. The fractions\' phenolic acid profile was characterized by gaseous chromatography, identifying the following phenolic acids ( eu acrescentaria: with antioxidant activity, ou antioxidant potential]: salicylic, ferulic coffeic, synaptic, chlorogenic quinic, p-cusmaric ,gentisic and protocatechinic . No statistic differences were obtained in sensorial evaluation of coffee infusion between more intensely roasted samples, which are close to those of commercial samples (p> 0.05). Based on these results the 180&#186;C/10 min sample was used in evalution of antioxidative potential in vivo . For this purpose Wistar rats received a daily dietary complement of different doses of roasted (180&#186;C/10 min) coffee aqueous extract. Administered doses were efficient in avoiding oxidation of plasmatic, hepatic, cerebral and cardiac tissues as evaluated by the TBARS method (substances reactive to thio-barbituric acid) a dosis-response effect being observed for all but the cardiac tissue (p> 0.05). The plasmatic lipidic profile of supplemented animals also indicated efficiency in oxidation inhibition of poli-unsaturated fatty-acids as compared to control group results (p> 0.05). The data presented suggest the potential usefulness of aqueous coffee extract as an antioxidant, when administered as an additive as well as consumed as a beverage, since the aqueous extract had the highest antioxidative activity.

Diferentemente do que muitos imaginam, o Brasil é detentor da maior diversidade de espécies de bambus dos países do Novo Mundo. O conhecimento sobre o potencial de aplicações de bambus nativos é extremamente subdesenvolvido em comparação ao de espécies asiáticas. Considerando que as espécies asiáticas são utilizadas na medicina popular e se têm relatos de várias atividades biológicas atribuídas à presença de flavonoides e outras substâncias fenólicas de interesse, espécies de bambu do Neotrópico são potenciais fontes de bioativos. Utilizando-se essa premissa, Merostachys pluriflora, uma espécie nativa de bambu, foi escolhida como modelo de estudo. Este trabalho teve como objetivos quantificar o teor de amido, carboidratos solúveis, lipídeos, fenóis totais, flavonoides, taninos totais e proantocianidinas de folhas e colmos de M. pluriflora; e avaliar o potencial biológico dos seus extratos, fases e substâncias isoladas através de ensaios in vitro da capacidade antioxidante, anti-HIV-1 e antibacteriana. Foi possível observar que o extrato bruto de folhas rendeu o dobro do extrato de colmo e que as fases obtidas com solventes mais polares, como a fase hidrometanólica, apresentaram maiores rendimentos. Dos metabólitos primários quantificados em M. pluriflora, os lipídeos se destacaram em conteúdo em ambos os órgãos estudados. Com relação as substâncias fenólicas, foi possível observar que o extrato bruto dos colmos apresentou uma maior abundância de fenilpropanoides e derivados do ácido clorogênico, enquanto o extrato bruto das folhas apresentou uma maior abundância de flavonoides, quando comparadas aos colmos. Das substâncias fenólicas presentes em M. pluriflora, foram identificadas duas flavonas, a vitexina e a isovitexina; e três fenilpropanoides, o ácido cafeíco, ácido ferúlico e o cafeato de metila. Das fases geradas por partição, a de acetato de etila e de diclorometano, para ambos os órgãos, foram as que apresentaram a maior parte dos constituintes fenólicos, sendo as fases de acetato de etila mais ricas em flavonoides e as de diclorometano em fenilpropanoides. No geral, os extratos brutos, assim como as fases de folhas e colmos de M. pluriflora, apresentaram um grande potencial antioxidante, principalmente antiradicalar e redutor de ferro, apresentando valores de EC50 de 16,30 &mu;g/mL a 94,77 &mu;g/mL no ensaio ABTS, no ensaio FRAP esses valores variaram de 27,92 &mu;g/mL a 145,78 &mu;g/mL. No ensaio antibacteriano, especialmente frente à P. pally, a fase de diclorometano de folhas se mostrou mais ativa, com MIC50 de 126,22 &mu;g/mL o que pode indicar que as substâncias fenólicas de caráter lipofílico, nessa espécie, são promissoras para essa atividade. Embora o ensaio anti-HIV1 mostrou que as amostras não apresentam atividade antirretroviral, este estudo contribui para o conhecimento do potencial antiviral dos extratos de bambus brasileiros. M. pluriflora se mostrou uma espécie promissora para estudos de prospecção, com uma grande quantidade de substâncias fenólicas em sua composição / Brazil is the country with the highest diversity of bamboo species in the New World. Knowledge about the medicinal potential of native bamboos is extremely underdeveloped when compared to Asian species. Some Asian bamboo species are used in folk medicine and have reports of various biological activities attributed to the presence of phenolic compounds, so bamboo species of the Neotropics are potential sources of bioactive substances. Using this assumption, Merostachys pluriflora, a native bamboo species, was chosen as a model for this study. The aimed of this study was to quantify the contents of starch, soluble carbohydrates, lipids, total phenols, flavonoids, total tannins and proanthocyanidins in leaves and culms of M. pluriflora; and evaluate the biological potential of the extracts, phases and isolated substances through in vitro assays: antioxidant activity, anti-HIV1 and antibacterial activity. It was observed that the crude extract of leaves yielded twice more than the culm extract; phases obtained with more polar solvents, such as hydromethanolic phases, had the highest yields. Lipids were the class of primary metabolites that presented higher quantities on both organs studied. Regarding the phenolic substances, it was observed that the crude extract of culms presented higher abundance of phenylpropanoids and chlorogenic acid derivates, but the crude extract from leaves showed higher abundance of flavonoids (all of then derived from apigenin) when compared to culms. Were identified two flavones, vitexin and isovitexin, and three phenylpropanoids, caffeic acid, ferulic acid and methyl caffeate. Phases using ethyl acetate and dichloromethane as extraction solvents were those that retained the majority of phenolic constituents. Ethyl acetate phase presented flavonoids while dichloromethane phase presented phenylpropanoids as major contituients. In general, the crude extracts and phases from leaves and culms of M. pluriflora showed antioxidant activity, especially antiradical and iron reducer capacity, presenting EC50 values of 16.30 mg/mL to 94.77 mg/ml in ABTS assay. For FRAP assay these values ranged from 27.92 mg/mL to 145.78 mg/mL. In the antibacterial assay, especially for P. pally, the dichloromethane phase from leaves was more active, presenting MIC50 of 126.22 mg/mL. This might indicate that the lipophilic phenolic present in this species of bamboo are promising for antibacterial activity. Although the anti-HIV1 assay showed that the samples do not present antiretroviral potential, this study contributes to the knowledge of the antiviral potential of Brazilian bamboo species. M. pluriflora showed to be a promising species for prospecting studies, with a large amount of phenolic substances in its composition

O consumo de dieta hiperlipídica e consequente acúmulo de lipídios nos adipócitos é uma condição associada ao estresse oxidativo e à perpetuação de um quadro inflamatório de leve intensidade que leva ao desenvolvimento de doenças crônicas não transmissíveis. Uma vez que alguns componentes da dieta são reconhecidos como fortalecedores do sistema antioxidante exógeno dos organismos vivos, o objetivo deste trabalho foi investigar o efeito metabólico do extrato de sementes do gênero Passiflora sobre parâmetros bioquímicos, oxidativos e inflamatórios de camundongos submetidos a uma dieta hiperlipídica. Para tanto, inicialmente realizou-se um estudo de composição química (centesimal, teores de minerais e ácidos graxos) e de otimização da extração de sementes de P. edulis Flavicarpa para obtenção de maiores teores de compostos polifenólicos com expressiva capacidade antioxidante in vitro, segundo os parâmetros de processo tempo, temperatura e concentração de etanol. Determinada a condição ideal de extração, esta foi empregada para as demais espécies em estudo P. alata BRS Mel do Cerrado e BRS Doce Mel, P. tenuifila BRS Vita e P. edulis BRS Sol do Cerrado e BRS Gigante Amarelo e P. setacea BRS Pérola do Cerrado e foi realizada o estudo de composição química. Os extratos etanólicos obtidos possuíram interessante atividade antioxidante, com destaque para a espécie P. setacea. O composto piceatanol foi o polifenol majoritário (0,41-10,28 g/ 100 g de semente em base seca) nas sementes de Passifloras analisadas, com exceção para a amostra P. setácea BRS Vita, cujo composto de íon molecular m/z 747,2 não foi identificado. As sementes ainda apresentaram alto teor de óleo, com o ácido linoleico em sua composição, e proteína. Os extratos das sementes de P. setacea BRS Pérola do Cerrado e Passiflora edulis Flavicarpa, nas concentrações de 500 e 1000 mg/Kg de ração foram utilizados para a realização do ensaio biológico. O consumo dos extratos, dependendo da dose, apresentou efeitos biológicos importantes, tais como a diminuição das concentrações séricas de colesterol, glicose, insulina e leptina a níveis aproximados ao determinado para os animais em consumo de dieta normolipídica. Adicionalmente, verificou-se a atenuação do estresse oxidativo hepático, por elevação da atividade enzimática das enzimas catalase e glutationa peroxidase e diminuição da lipoperoxidação, e do processo inflamatório, por redução da concentração tecidual das citocinas IL-6 e MCP-1. Os resultados obtidos neste estudo contribuem para o conhecimento a respeito das passifloras brasileiras e na potencial utilização das sementes, consideradas subprodutos, na contribuição da manutenção da saúde. / The consumption of a high fat diet and consequent excessive lipid accumulation in adipocytes is a condition associated with oxidative stress and perpetuation of a mild inflammatory condition that leads to the development of chronic diseases. Since some dietary components are recognized as empowering exogenous antioxidant system defenses of living organisms, the aim of this study is to investigate the metabolic effects of passion fruit seeds that possess a high content of bioactive compounds and high antioxidant capacity in vitro on oxidative stress and inflammatory conditions in mice subjected to a high fat diet. For this purpose, initially were performed a chemical composition study (proximate, minerals and fatty acids content) and extraction optimization of P. edulis Flavicarpa seed for obtaining higher levels of polyphenolic compounds with expressive antioxidant capacity in vitro through process parameters such as time temperature and ethanol concentration. Once the optimum condition of extraction was determined, it was applied to others studied species P. alata BRS Mel do Cerrado e BRS Doce Mel, P. tenuifila BRS Vita e P. edulis BRS Sol do Cerrado e BRS Gigante Amarelo e P. setacea BRS Pérola do Cerrado and the chemical composition study was carried out. The obtained ethanolic extracts had high antioxidant activity, particularly the species P. setacea. The piceatannol compound was the major polyphenol (0.41 to 10.28 g / 100 g seed in dry basis) in the analyzed Passiflora, except for the sample P. setacea BRS Vita, which molecular íon m/z 747.2 was not identified. The seeds also showed high content of oil, with linoleic acid in its composition, and protein. P. setacea BRS Pérola do Cerrado and Passiflora edulis Flavicarpa seed extracts at concentrations of 500 and 1000 mg / kg of feed were used to carry out the biological assay. The consumption of the extracts, depending on the concentration, exhibited significant biological effects, such as the reduction of serum cholesterol, glucose, insulin and leptin levels to those one observed in animals with normolipidic diet consumption. Additionally, hepatic oxidative stress was attenuated by elevating enzymatic activity of catalase and glutathione peroxidase and decrease in the lipid peroxidation and inflammation by reducing the tissue concentrations of IL-6 and MCP-1 cytokines. The results obtained in this study contributes to the knowledge of the Brazilian passiflora and potential use of the seeds, considered a by-products, in health maintenance.

Este trabalho teve como objetivo contribuir para o desenvolvimento de um processo de destoxificação biológica do hidrolisado hemicelulósico de bagaço de cana-de-açúcar utilizando as leveduras Issatchenkia occidentalis CCTCC M 206097 e Issatchenkia orientalis CCTCC M 206098. Com este propósito, foi realizado testes com diferentes concentrações de hidrolisado hemicelulósico de bagaço de cana-de-açúcar e diferentes condições experimentais para avaliar a influência do fator de concentração e pH inicial do hidrolisado, temperatura e agitação do sistema, na eficiência da redução na concentração de compostos inibidores presentes no hidrolisado de bagaço de cana-de-açúcar, sem a redução na concentração de açúcares. As leveduras avaliadas apresentaram os maiores valores de redução na concentração dos inibidores e uma menor perda de açúcares quando utilizado o hidrolisado com fator de concentração 5. Nestes experimentos foram constatados que o aumento na concentração de D-glicose e D-xilose favoreceram o menor consumo destes açúcares por estas leveduras. Foi observado também que após 24 h de ensaio empregando a levedura I. occidentalis a redução na concentração de siringaldeído (66,67%) e ácido ferúlico (73,33%) foi maior quando destoxificado o hidrolisado concentrado. Entretanto, nestas mesmas condições ao empregar a levedura I. orientalis foi verificado uma redução maior na concentração de 5-hidroximetilfurfural (80%) e furfural (56,25%). Com base no potencial de redução destes compostos inibidores em hidrolisado de bagaço de cana-de-açúcar concentrado, foram realizados estudos para avaliar a influência do pH inicial do hidrolisado (4,0 a 7,0), temperatura (23 a 37°C) e agitação do sistema (100 a 300 rpm) na porcentagem de redução da concentração do total de inibidores, utilizando um planejamento fatorial 23 com 3 repetições no ponto central. De acordo com os resultados, verificou-se que independente do microrganismo utilizado como agente destoxificante do hidrolisado de bagaço de cana-de-açúcar a maior porcentagem de redução na concentração dos inibidores totais foi obtida ao empregar todos os fatores avaliados em seus níveis inferiores. Os resultados obtidos neste trabalho demonstraram o potencial das leveduras Issatchenkia occidentalis CCTCC M 206097 e Issatchenkia orientalis CCTCC M 206098 como agentes destoxificantes de hidrolisado hemicelulósico de bagaço de cana-de-açúcar. / This work had as the main objective contribute for the development of a biological detoxification of sugarcane bagasse hydrolysate using the Issatchenkia occidentalis CCTCC M 206097 and Issatchenkia orientalis CCTCC M 206098 yeasts. With this aim, it was done tests with hemicellulosic hydrolysate of sugarcane bagasse in different concentrations and different experimental conditions to evaluate the influence of the hydrolysate concentration, icicial pH of the hydrolysate, temperature and system agitation, on the efficiency of concentration reduction of inhibitory compound present in the sugarcane bagasse hydrolysate, without sugar concentration reduction. The evaluated yeasts showed more redutction values on the the inhibitors concentration and less sugar losses when it was used the hydrolysate five fold concentrated. At these experimets it was found that the concentration rise of D-glucose and D-Xylose favored a lower sugar consumption by the yeasts. It was also observed that after 24 h of experiment using I. occidentalis yeast the reduction of syringaldehyde concentraction (66,67%) and ferulic acid concentration (73,33%) was higher when the concentrated hydrolysate was detoxified. However, under the same conditions using I. orientalis it was observed a higher reduction on the 5-hydroxymethylfurfural (80%) and furfural (56,25%). Based on the potential reducion of these inhibitors in concentrated sugarcane bagasse hydrolysate, it was performed studies to evaluate the influence of initial pH (4,0 or 7,0), temperature (23 to 37°C) and system agitation (100 to 300 rpm) on the reduction percentage of total inhibitors concentration, using a factorial experimental design 23 with three repetitions in the central point. According to the results, it was observed that independent of the microrganism used as detoxificant agent of the sugarcane bagasse hydrolysate, the largest reduction percentage of the total inhibitors concentration was obtained using all the factors evaluated in their low levels. The results obtained in this work showed the potential of the yeasts Issatchenkia occidentalis CCTCC M 206097 and Issatchenkia orientalis CCTCC M 206098 asdetoxificant agent of hemicellulosic hydrolysate of sugarcane bagasse.