Bluberries (Vaccinium sp.) are rich in polyphenols that are responsible for lowering the risk of developing several chronic degenerative diseases. However, the effect of food matrix interactions on the bioaccessibility and bioavailability of polyphenols is not well understood. In this research free and complexed polyphenols found in blueberry extracts were characterized and their antioxidant activity as well as antiproliferative activities against colon cancer cells (HT-29) and normal colon cells (CRL-1790) were evaluated. The blueberry food matrix and different carbohydrate-rich synthetic matrices were characterized and their biological activities assessed alone and in complexed state with polyphenols. The degradation of polyphenols during their transit through the gastrointestinal tract (GIT) was evaluated using an in vitro digestion model. Biological activities of blueberry polyphenols and their parent metabolites produced during colonic fermentation were estimated by in vitro antioxidant assays and cell proliferation analysis using HT-29 and CRL-1790 cell lines. HPLC analysis revealed the presence of 7 phenolic compounds and 13 anthocyanins in all samples. Although the concentration of the polyphenols varied among the samples, free and complexed polyphenols showed significant antioxidant and antiproliferative activities. Polyphenol complexes were analyzed using transmission electron microscopy (TEM) revealing the presence of electron dense complexes ranging from 100 – 200 nm. Pectinase treatment disrupted the structure of the complexes, suggesting the pectin nature of the polyphenol complexes. The antioxidant- and antiproliferative activities of the blueberry food matrix alone was below 10% compared to almost 90% and 70% of free and complexed polyphenols, respectively. Polyphenols and anthocyanins were highly stable during simulated gastric digestion step with approximately 93% and 99% of recovery, respectively. The intestinal digestion process decreased the polyphenol- and anthocyanin- contents by 49% and 15 % respectively. During colonic digestion, the complex polyphenol mixtures were degraded to a limited number of phenolic compounds. Only acetylated anthocyanins were detected in low amounts after the colonic digestion process. After simulated colonic digestion, the isolated catabolites showed lowered antioxidant activity and cell growth inhibition potential. Understanding the interactions that occur among polyphenols and different food matrices may help to produce more stable foods with better bioavailability. / The National Council of Science and Technology of Mexico (CONACYT)

A static in vitro digestion method was developed as a strategy to understand the effects of modelled digestion on the solubility of nutrients and selected bioactive compounds of autoclaved and untreated wheat bran. Brans from common soft, hard, and durum wheats were evaluated. Results indicated that the in vitro digestion protocol was suitable and effective. Effects of gastrointestinal simulation were considerably larger than gastric digestion alone. Digestibility of the brans ranged from 28.1 to 47.9%. Digestibility of bran minerals, starch and protein was substantial compared to lesser, but still significant, effects on fibre. Fibre solubility was significantly enhanced due to autoclaving. Total phenolic content, free radical scavenging and metal chelation activity were all substantially increased in soluble digests. Yields of these factors indicated that digestion of wheat bran releases ample levels of antioxidants that would be available for absorption in the small intestine to promote beneficial health effects.

Content of free- (FPC) and bound- phenolics (BPC) significantly (p<0.05) increased during mixing, fermenting and baking. Bread crust and crumb contained the highest FPC and BPC, respectively. Antioxidant activities (AOA) followed the trends of their respective phenolic contents. HPLC analysis demonstrated that different phenolic acids showed various responses to the bread-making process. Total anthocyanin content (TAC) was significantly (p<0.05) reduced through mixing and baking, but fermentation elevated the levels. Anthocyanin extract of purple wheat exerted higher AOA than those of common wheat. Digested purple wheat extracts after in-vitro digestion demonstrated significantly (p<0.05) higher AOA than common wheat. During in-vitro testing, extracts exhibited concentration-dependent effects, while the use of different cell lines exhibited varying levels of cellular antioxidant and pro-oxidant properties. Purple wheat demonstrated higher cytoprotectivity and cellular AOA than those of common wheat. Our findings suggest that purple wheat has the potential to act as functional food in bakery products.

A static in vitro digestion method was developed as a strategy to understand the effects of modelled digestion on the solubility of nutrients and selected bioactive compounds of autoclaved and untreated wheat bran. Brans from common soft, hard, and durum wheats were evaluated. Results indicated that the in vitro digestion protocol was suitable and effective. Effects of gastrointestinal simulation were considerably larger than gastric digestion alone. Digestibility of the brans ranged from 28.1 to 47.9%. Digestibility of bran minerals, starch and protein was substantial compared to lesser, but still significant, effects on fibre. Fibre solubility was significantly enhanced due to autoclaving. Total phenolic content, free radical scavenging and metal chelation activity were all substantially increased in soluble digests. Yields of these factors indicated that digestion of wheat bran releases ample levels of antioxidants that would be available for absorption in the small intestine to promote beneficial health effects.

Doctor of Philosophy / Department of Human Nutrition / Brian Lindshield / Fortified blended foods (FBFs), in particular, corn-soybean blend (CSB), are food aid commodities widely used in infant and young children supplementary feeding programs. A United States Agency for International Development (USAID) Food Aid Quality Review report recommended developing novel FBFs using local alternative commodities such as sorghum and improving the nutritional quality of FBFs using extrusion processing. Extruded sorghum-cowpea, sorghum-soy and corn-soy FBFs were developed and compared with the non-extruded FBFs corn-soy blend 13 (CSB13) and corn-soy blend plus (CSB+) using the in-vitro digestion/Caco-2 cell model. Dry FBFs’ iron and vitamin A content ranged from 8.0 to 31.8 mg/100g and 0.54 to 1.67 mg/100g, respectively. Following in-vitro digestion, bioavailable iron and vitamin A levels were determined by measuring Caco-2 cell ferritin and vitamin A levels in response to 12-hour and 4-hour treatments, respectively, with aqueous fractions collected from digested FBFs. Most extruded FBFs’ aqueous fraction iron levels were 2- to 7-fold higher (p<0.05) than CSB13 and CSB+. However, Caco-2 cell ferritin and vitamin A levels were not significantly different among FBFs. These results suggest that consumption of newly developed extruded sorghum-cowpea, sorghum-soy and corn-soy FBFs will result in bioavailable iron and vitamin A levels comparable to traditional non-extruded CSB13 and CSB+. Thus, extruded sorghum-cowpea FBF may be a suitable alternative to corn-soybean based FBFs. Saw palmetto supplements are one of the most commonly consumed products by men with prostate cancer and/or benign prostatic hyperplasia (BPH). Some studies have found significant improvements in BPH with saw palmetto supplementation, whereas others found no benefits. The variation in the efficacy in these trials may be a result of differences in the putative active components, fatty acids and phytosterols, of the saw palmetto supplements. We quantified fatty acids and phytosterols in 20 commercially available liquid, powder, dried berry, and tincture saw palmetto supplements. Liquid saw palmetto supplements contained significantly higher (p<0.05) concentrations of total fatty acids (908.5 mg/g), individual fatty acids, total phytosterols (2.04 mg/g), and individual phytosterols, than the other supplement categories. Our findings suggest that liquid saw palmetto supplements may be the best choice for individuals who want to take a saw palmetto supplement.

Orientador: Flavia Maria Netto / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-10T19:43:01Z (GMT). No. of bitstreams: 1 Pazinatto_Caroline_M.pdf: 872603 bytes, checksum: 24b721ce9b9486921e2492870c2452f0 (MD5) Previous issue date: 2008 / Resumo: O amaranto se destaca por seu perfil protéico, rico em aminoácidos essenciais e pela presença de outros compostos tais como: fibras, esqualeno, tocoferóis, tocotrienóis e compostos fenólicos, que lhe confere propriedades especiais, incluindo propriedade antioxidante. A fácil adaptação da planta a diferentes condições climáticas, juntamente com as suas qualidades nutricionais e funcionais, aumentam o interesse em introduzir a cultura do amaranto no Brasil. Apesar de bem caracterizado quimicamente e de apresentar compostos com potencial fisiológico, poucos estudos foram realizados para avaliar o potencial do grão de amaranto como alimento funcional. O presente trabalho tem como objetivo avaliar a capacidade antioxidante dos diferentes produtos obtidos a partir do grão integral de amaranto (Amaranthus cruentus). Após a moagem e o desengorduramento dos grãos para a obtenção da farinha desengordurada, diferentes processos, incluindo a hidrólise com Alcalase, foram utilizados na produção dos diversos produtos de amaranto que foram posteriormente digeridos in vitro com as enzimas pepsina e pancreatina. Os efeitos dos processos e da digestão in vitro das frações protéicas, e o efeito dos compostos fenólicos totais na capacidade antioxidante, em extrato aquoso e metanólico, foram avaliados utilizando o ensaio da capacidade seqüestradora de radicais DPPH e o ensaio de ORAC. O teor de fenóis totais apresentou elevada correlação com a capacidade antioxidante quando avaliada no extrato metanólico. Entretanto, a correlação foi menor quando avaliada no extrato aquoso, sugerindo que os compostos hidrossolúveis podem interferir nas avaliações. A hidrólise com Alcalase elevou significativamente o potencial antioxidante das amostras, de 2 a 4 vezes a capacidade seqüestradora de radicais DPPH e de 13 a 15 vezes os valores de ORAC. A digestão in vitro aumentou a capacidade antioxidante medida por ambos os ensaios (até 7 vezes para a capacidade seqüestradora de radicais DPPH e 12 para o valor de ORAC), especialmente para o concentrado protéico e seus hidrolisados. O elevado teor de fenóis totais liberados e o aumento da capacidade antioxidante dos produtos de amaranto após a digestão in vitro sugerem que o mesmo ocorre após a digestão fisiológica. Os resultados sugerem que a inclusão de produtos de amaranto na dieta, especialmente concentrado protéico e seus hidrolisados, pode promover benefícios à saúde / Abstract: Amaranth is well known for its protein profile, rich in essential amino acids and the presence of other compounds such as fiber, squalen, tocols (tocopherols and tocotrienols) and phenolic compounds that are responsible for its special properties, including antioxidant capacity. The easy adaptation of the plant to different climate conditions, together with its nutritional qualities and functional properties, increase the interest to introduce the culture of amaranth in Brazil. Despite being well characterized chemically and exhibiting compounds with physiological potential, few studies have been conducted to evaluate the potential of amaranth grain, as a functional food. This study aims to evaluate the antioxidant capacity of different products obtained from amaranth grain (Amaranthus cruentus). After milling and defatting the grain to obtain deffated amaranth flour, different processes, including Alcalase hydrolysis, were used to produce a variety of products that were digested in vitro with pepsin and pancreatin. The effects of the processes and of the digestion in vitro of the protein fractions, and the effect of the total content of phenolic compounds on the antioxidant capability in aqueous and methanolic extracts were evaluated using scavenging capacity of DPPH radical and ORAC assays. Total phenolic compounds content showed high correlation with the antioxidant capacity, when evaluated in methanolic extract. However, the correlation was lower when using the aqueous extract, suggesting that water soluble compounds may interfere in these evaluations. Hydrolysis with Alcalase increased significantly the antioxidant potencial, from 2 to 5 times the scavenging DPPH capacity and 13 to 15 the ORAC values. In vitro digestion increased the antioxidant capacity measured by both assays (up to 7 times for scavenging DPPH capacity and 12 times for ORAC assays), especially for protein concentrate and its hydrolysates. The high content of phenolic compounds released and the increase in antioxidant capacity after in vitro digestion of the amaranth products suggests that the same occurs after the physiological digestion. These results suggest that the inclusion of these products, especially concentrate and its hydrolysates, in the diet should promote health benefits / Mestrado / Nutrição Experimental e Aplicada à Tecnologia de Alimentos / Mestre em Alimentos e Nutrição

Tendo em vista a importância dos compostos bioativos (CBAs) para a promoção da saúde, foram desenvolvidos, a partir de cruzamentos do tomate cereja com espécies selvagens, os tomates laranja (rico em &#946;-caroteno) e roxo (rico em antocianinas), por meio da técnica de introgressão de alelos. Diante disso, o objetivo deste trabalho foi caracterizar o perfil de compostos bioativos e voláteis dos tomates enriquecidos e avaliar a estabilidade e metabolização de flavonoides do tomate roxo durante digestão in vitro e em modelo animal. Os tomates foram caracterizados quanto ao conteúdo de compostos fenólicos totais; capacidade antioxidante por DPPH e ORAC; ácidos orgânicos; açúcares solúveis; perfil de carotenoides por CLAE/DAD; flavonoides por CLAE/DAD e LC/ESI/MS/MS e compostos voláteis por CG/MS. Avaliou-se ainda a estabilidade dos flavonoides da casca do tomate roxo por simulação da digestão in vitro, utilizando o Simulator of the Human Intestinal Microbial Ecosystem (SHIME), bem como a formação de AGCC por GC-MS, e excreção em ratos Wistar, com posterior identificação dos compostos fenólicos por LC/Q-TOF/MS. O tomate roxo apresentou aumento no conteúdo de fenólicos totais, capacidade antioxidante e vitamina C, com destaque para casca. A rutina foi o principal flavonol identificado em todos os frutos, e na casca do tomate roxo foi encontrado alto teor de petunidina (p-coumaroil)-rutinosídeo-hexosídeo, além da superexpressão de outros flavonoides como a quercetina-3-O-rutinosídeo e kaempferol. Não houve alteração no perfil de flavonoides do fruto laranja. Este, por sua vez, apresentou acúmulo de &#946;-caroteno, importante pró-vitamina A, ao passo que o tomate roxo também teve seus conteúdos de &#946;-caroteno e licopeno aumentados. Os frutos apresentaram perfil de compostos voláteis diferentes entre si, o que foi relacionado à degradação dos diferentes CBAs característicos de cada um. O extrato fenólico da casca de tomate roxo, submetido à digestão in vitro, se manteve estável na primeira porção, relativo às condições estomacais. Contudo, o conteúdo de flavonoides apresentou redução significativa (p<0,05) nas porções que simulam as condições do duodeno e do colón, com a formação de catabólitos pela ação da microbiota intestinal e/ou pela degradação química espontânea. Foi observado o aparecimento de novos ácidos fenólicos não presentes inicialmente na matriz, dentre eles o ácido 3-O-metilgálico e o ácido homovanílico, supostamente derivados da degradação da petunidina e da quercetina, respectivamente. Houve aumento na produção total de AGCC, com excessão do butirato. Na urina dos animais foram detectados diversos outros compostos fenólicos derivados do metabolismo de fase II, dentre eles o ácido hipúrico e o 3-O-metilcatecol. Nas fezes foram identificados cerca de metade dos compostos presentes na fermentação in vitro. Dessa forma, o melhoramento convencional pode ser uma alternativa para o enriquecimento, com CBAs, de alimentos amplamente consumidos pela população, como o tomate. Além disso, durante a passagem pelo trato gastrointestinal, os flavonoides presentes na casca do tomate roxo sofrem intensa degradação pela microbiota intestinal, com formação de catabólitos com reconhecido potencial benefício à saúde. / Considering the importance of bioactive compounds (BACs) for health promotion, the orange (&#946;-carotene-rich) and purple (anthocyanin-rich) tomatoes were developed from cherry tomato interspecific crossing with wild species, using the technique of allele introgression. The objective of this work was to characterize the profile of bioactive and volatile compounds of enriched tomatoes, and to evaluate the stability and metabolism of purple tomato\'s flavonoids during in vitro and in vivo digestion. The tomatoes were characterized by its content of total phenolic compounds; antioxidant capacity (DPPH and ORAC); organic acids; soluble sugars; carotenoids (HPLC/DAD); flavonoids (HPLC/DAD and LC/ESI/MS/MS) and volatile compounds (GC/MS). The stability of the flavonoids from purple tomato peel was assessed by using the Simulator of the Human Intestinal Microbial Ecosystem (SHIME), as well as the formation of AGCC by GC-MS, and metabolism and excretion in Wistar rats, with subsequent identification of phenolic compounds by LC/Q-TOF/MS. The purple tomato showed an increase in the total phenolic content, antioxidant capacity and vitamin C, with highlight for the peel. The rutin was the main flavonol identified in all fruits, and it was found high content of petunidin (p-coumaryl)-rutinoside-hexoside in the purple tomato peel, in addition to overexpression of other flavonoids such as quercetin-3-O-rutinoside and kaempferol. There was no change in the flavonoid profile of the orange fruit. This one, in turn, presented accumulation of &#946;-carotene, important pro-vitamin A, while the purple tomato also showed an increase in its &#946;-carotene and lycopene contents. The fruits presented different volatile compounds profile among them, which was related to the degradation of the different BACs composition of each one. In the in vitro digestion, the phenolic extract of the purple tomato peel remained stable in the first portion, relative to the stomach conditions. However, the content of flavonoids presented a significant reduction (p<0.05) in the portions simulating the duodenum and colon, with the formation of catabolites by the action of intestinal microbiota and/or spontaneous chemical degradation. It was observed the appearance of new phenolic acids that was not initially present in the matrix, among them 3-O-methylgalic acid and homovanilic acid, supposedly derived from the degradation of petunidin and quercetin, respectively. There was an increase in the total production of SCFAs, with the exception of butyrate. In the urine of the animals several other phenolic compounds derived from phase II metabolism were detected, among them hippuric acid and 3-O-methylcatechol. About half of the compounds present in the in vitro fermentation were identified in the feces. Conventional breeding may be an alternative for the enrichment, with BACs, of foods that are widely consumed by the population, such as tomatoes. In addition, during the passage through the gastrointestinal tract, the flavonoids present in the purple tomato peel are severely degraded by the intestinal microbiota, with formation of catabolites with recognized potential health benefit.

Orientador: Rosiane Lopes da Cunha / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-19T15:16:51Z (GMT). No. of bitstreams: 1 Vilela_JoiceAlinePires_M.pdf: 1796773 bytes, checksum: 34d2e3b8b4543d7ea7cce06e84d31138 (MD5) Previous issue date: 2012 / Resumo: A encapsulação de muitos compostos bioativos, como vitaminas, bactérias probióticas e antioxidantes ajuda na incorporação, proteção, e entrega do bioativo em sítio específico, porém a eficiência da matriz carreadora depende da sua composição e processo de fabricação. Com este intuito, a viabilidade de produção e as características finais de microgéis de gelana formados por extrusão e posterior gelificação iônica foram estudadas. Micropartículas, com tamanho médio entre 70-120 ?m, foram produzidas sob condições amenas de temperatura e concentração, utilizando um processo de atomização seguido de gelificação em soluções de cloreto de cálcio (CaCl2), cloreto de potássio (KCl) ou quitosana. O tamanho das partículas mostrou-se mais dependente das condições de processo (geometria do bico aspersor e velocidade de ar) que das propriedades da solução biopolimérica. No entanto, o aumento da concentração de gelana levou a maior esfericidade dos microgéis obtidos. Com relação aos agentes gelificantes, as micropartículas com gelificação induzida por CaCl2 apresentaram formato mais esférico e maior estabilidade que as partículas formadas a partir de KCl. A obtenção de micropartículas de gelana recobertas com quitosana foi possível somente através de um processo em duas etapas. Na primeira etapa, a gelana foi gelificada através da difusão salina (CaCl2 ou KCl) e posteriormente, as partículas formadas foram recobertas com quitosana. A presença da camada externa de quitosana teve influência na resistência das partículas às condições simuladas da digestão. As partículas estudadas, com ou sem recobrimento de quitosana, resistiram à digestão gástrica, mas na digestão entérica as partículas recobertas com quitosana apresentaram menor grau de fragmentação que as partículas contendo somente gelana. Assim, foi demonstrado que a produção de microgéis formados por interação entre dois biopolímeros de cargas opostas melhorou a eficiência das partículas como material de parede sendo este um potencial veículo de compostos bioativos / Abstract: The encapsulation of many bioactive compounds such as vitamins, antioxidants and probiotic bacteria allows the incorporation, protection, and delivery of bioactive on a specific site, but the efficiency of carrier matrix depends on its composition and manufacturing process. To this aim, the feasibility of production and the final characteristics of the gellan microgels obtained by extrusion process followed by ionic gelation were studied. Microparticles, with average size among 70-120 ?m, were produced under mild conditions of temperature and concentration using an atomization process followed by gelation induced by calcium chloride (CaCl2), potassium chloride (KCl) or chitosan solutions. The particle size was more dependent on process conditions (nozzle geometry and air velocity) than the properties of the biopolymeric solution. However, the increase in gellan concentration led to more spherical microgels. In relation to hardening agents, the microparticles with gelation induced by CaCl2 showed more spherical shape and greater stability than the particles formed by KCl. Gellan microparticles coated with chitosan was possible to obtain only through a two-step process. In the first step, the gellan microgels were obtained through salt diffusion (KCl or CaCl2) and the particles obtained were subsequently coated with chitosan. The presence of the outer layer of chitosan exerted effect on the resistance of the particles to the simulated digestion process. All particles studied, with or without a coating of chitosan, resisted to the gastric digestion, however the chitosan coated particles showed a lower degree of fragmentation than the particles containing only gelan when subjected to the enteric digestion step. Therefore the results obtained showed that the microgels formed by interaction between two oppositely charged polymers improved the efficiency of particles as wall material, showing a great potential as bioactive compounds carrier / Mestrado / Engenharia de Alimentos / Mestre em Engenharia de Alimentos

Orientador: Gláucia Maria Pastore / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-26T14:43:49Z (GMT). No. of bitstreams: 1 Sancho_RenataAparecidaSoriano_D.pdf: 2230082 bytes, checksum: b2618836eaa99bfffc96d493f873e0a6 (MD5) Previous issue date: 2015 / Resumo: A ingestão de alimentos ricos em compostos bioativos está associada ao menor risco de doenças crônicas. Diferentes mecanismos estão envolvidos, principalmente através de seu potencial antioxidante. O objetivo deste estudo foi determinar a atividade antioxidante e os teores de diferentes compostos bioativos presentes nos extratos das cascas de feijão preto e roxinho e avaliar as propriedades antioxidantes e antidiabéticas do extrato rico em antocianinas de casca de feijão preto (ERA). Extratos de feijão preto e roxinho foram submetidos à digestão in vitro e avaliados através das determinações de fenóis totais, flavonoides totais, taninos condensados, antocianinas monoméricas e atividade antioxidante por meio de dois diferentes métodos. No ERA, as antocianinas foram identificadas e quantificadas por cromatografia líquida de alta eficiência acoplada a espectrômetria de massas. Antocianinas monoméricas, fenóis totais e atividade antioxidante através dos ensaios TEAC (Trolox Equivalent Antioxidant Capacity) e ORAC (Oxygen Radical Absorbance Capacity) também foram avaliados antes e após a digestão in vitro No ensaio in vivo, o efeito da administração do ERA foi investigado em ratos com Diabetes induzido por estreptozotocina. Ratos Wistar foram distribuídos em 5 grupos (controle normal, normal tratado com ERA, controle diabético, diabético pré-tratado com ERA e diabético pós-tratado com ERA) e tratados durante 3 semanas. Glicemia, peso corpóreo, perfis enzimáticos hepático e renal, histologia dos tecidos pancreático e hepático foram avaliados, além do potencial antioxidante, através da análise das enzimas catalase, glutationa redutase e do ensaio ORAC plasmático. O feijão preto apresentou uma concentração dez vezes maior de antocianinas que o feijão roxinho (0,83±0,04 e 0,08±0,01 mg equivalentes cianidina 3-glicosídeo/g). Após a digestão in vitro, as antocianinas não foram detectadas, os fenóis totais dos extratos de feijão preto e roxinho tiveram reduções respectivas de 75% e 52%. Os taninos condensados apresentaram redução de 90% em ambos os extratos. Na análise dos flavonoides, a concentração do feijão roxinho permaneceu inalterada e o feijão preto apresentou redução de 21%. O feijão roxinho apresentou maior capacidade de neutralização do radical ABTS que o feijão preto, com respectivos 21,9±0,5 e 17,4±0,1 µM equivalentes Trolox/g. A digestão in vitro não afetou a capacidade antioxidante dos extratos analisados por este método. No ensaio ORAC, os feijões apresentaram aumento da capacidade antioxidante com 43,2% e 32,6% para os feijões preto e roxinho, respectivamente. Delfinidina 3-glicosídeo, petunidina 3-glicosídeo e malvidina 3-glicosídeo foram identificadas no ERA. A digestão provocou decréscimo de 90% na concentração das antocianinas e de 45% nos fenóis totais. A atividade antioxidante no ensaio TEAC foi reduzida em 28% e no ensaio ORAC em 35%. O ensaio in vivo mostrou os efeitos protetores do ERA apenas no grupo pré-tratado, com melhora dos níveis da glicemia e ganho de peso. Neste mesmo grupo, alterações pancreáticas, hepáticas e renais foram menos acentuadas do que nos outros grupos diabéticos. O tratamento com ERA, subsequente à indução do Diabetes não reduziu os danos teciduais, as alterações biológicas ou melhorou o estado geral dos animais. Neste modelo experimental, o pré-tratamento com ERA reduziu os danos causados pelo Diabetes induzido por estreptozotocina / Abstract: The food intake rich in bioactive compounds is associated with a reduced risk of chronic diseases. Different mechanisms are involved, especially through their antioxidant potential. The goal of this study was to determine the antioxidant activity and the concentrations of different bioactive compounds present in extracts of black and small red beans seed coats and to evaluate the antioxidant and antidiabetic properties of anthocyanin-rich extracts from black bean seed coats (ERA). Black and small red beans extracts were subjected to in vitro digestion and evaluated through analyzes of total phenolics, total flavonoids, condensed tannins, monomeric anthocyanins and antioxidant activity by two different methods. In ERA, anthocyanins have been identified and quantified by high performance liquid chromatography coupled to mass spectrometry. Monomeric anthocyanins, total phenolics and antioxidant activity through TEAC (Trolox Equivalent Antioxidant Capacity) and ORAC (Oxygen Radical Absorbance Capacity) assays were also assessed, before and after in vitro digestion. At the in vivo assay, the effect of ERA administration was investigated in rats with streptozotocin-induced diabetes. Wistar rats were distributed into 5 groups (normal control, normal treated with ERA, diabetic control, diabetic pre-treated with ERA and diabetic post-treated with ERA) and treated for 3 weeks. Blood glucose, body weight, liver and kidney enzyme profiles, pancreas and liver tissue histology were evaluated, as well as the antioxidant potential through analysis of catalase, glutathione reductase, and ORAC plasmatic assay. Black beans showed tenfold higher concentrations of anthocyanins than small red beans (0.83±0.04 e 0.08±0.01 mg cyanidin 3-glucoside equivalent/g). After in vitro digestion, anthocyanins could not be detected, and total phenols of black and small red beans have respective reductions of 75% and 52%. Condensed tannins decreased by 90% in both extracts. On the flavonoids analysis, while the concentration in small red beans remained unchanged, black beans showed a reduction of 21% in their concentration. Small red beans showed higher ABTS radical scavenging capacity than black beans, with respective 21.9±0.5 and 17.4±0.1 µM Trolox equivalents/g of bean. In vitro digestion did not affect the antioxidant activity of the analyzed extracts by this method. In the ORAC assay, both beans showed an increase in the antioxidant capacity, with 43.2% and 32.6% for black and small red beans, respectively. Delphinidin 3-glucoside, petunidin 3-glucoside and malvidin-3-glucoside were identified in ERA. Digestion triggered a decrease of 90% in monomeric anthocyanins concentration and of 45% in total phenolic contents. The TEAC assay antioxidant activity was reduced by 28% and the ORAC one by 35%. The in vivo assay showed protective effects of ERA only in the pre-treated group, with improvement of the glycemia levels and the weight gain. Also for the same group, pancreatic, hepatic and renal changes were less marked than in the others diabetics groups. ERA treatment subsequent to the induction of diabetes did not reduce the tissue damages, the biological alterations or improve the animals¿ general state. In this experimental model, pre-treatment with ERA reduced the damages caused by streptozotocin induced diabetes / Doutorado / Ciência de Alimentos / Doutora em Ciência de Alimentos

Diversos estudos com compostos fenólicos têm demonstrado os efeitos benéficos destas substâncias frente a diversas patologias, incluindo alguns tipos de câncer. Considerando que os polifenóis da dieta, não absorvidos, podem permanecer no trato gastrointestinal por um período prolongado, e as células do epitélio intestinal podem ser regularmente expostas a estes compostos, é importante avaliar seu potencial efeito benéfico no trato gastrointestinal. Entretanto, é necessário determinar como o processo de digestão afeta a estabilidade e propriedades químicas destes compostos. O objetivo deste estudo foi avaliar a bioacessibilidade dos polifenóis de sucos de frutas da família Myrtaceae: cagaita (Eugenia dysenterica DC), camu-camu (Myrciaria dubia Mc Vaugh) e jaboticaba (Myrciaria cauliflora B.), o efeito da digestão gastrintestinal in vitro sobre sua atividade antioxidante, e a ação dos polifenóis dos sucos digeridos sobre a proliferação, ciclo celular e apoptose em células Caco-2 de adenocarcinoma de cólon humano. A digestão simulada in vitro causou perdas de alguns compostos, tais como os derivados de cianidina encontrados na jaboticaba, possivelmente devido às condições do pH intestinal. No entanto, o conteúdo de ácido elágico livre aumentou em todos os sucos analisados, indicando a ocorrência de hidrólise durante o processo de digestão in vitro, liberando ácido elágico a partir dos elagitaninos. A atividade antioxidante dos polifenóis foi afetada de forma diferente pela digestão in vitro, de acordo com o suco, provavelmente relacionado à composição de polifenóis. Quanto à proliferação, ciclo celular e apoptose, os polifenóis a partir da fração bioacessível do camu-camu apresentou aproximadamente 30% de inibição da proliferação, seguido pela cagaita com 24%, ambos na maior concentração testada (50 &#181;g EAG/mL). Jaboticaba não apresentou efeito inibitório nas concentrações testadas, entretanto os compostos fenólicos de todas as frações bioacessíveis (50 &#181;g EAG/mL) apresentaram parada no ciclo celular na fase G2/M sem induzir apoptose nas células Caco-2. Os resultados sugerem que os polifenóis das Myrtaceae podem modular a proliferação nas células Caco-2 por bloqueio da progressão do ciclo celular na fase G2/M e assim oferecer efeitos benéficos para a saúde do trato gastrointestinal. / Several studies with phenolic compounds have shown the beneficial effects of these substances across various diseases, including some types of cancer. Considering that most of the polyphenols and their conjugates, unabsorbed, can remain in the lumen for a prolonged period, and epithelial cells lining the intestine are regularly exposed to these compounds, it is important to evaluate their potential beneficial effects in the gastrointestinal tract. However it is necessary to evaluate how the digestion process affects the stability and chemical properties of these compounds. The aims of this study were to evaluate the bioaccessibility of polyphenols in juices from Brazilian native fruits of the Myrtaceae family (cagaita, camu-camu and jaboticaba), the effect of in vitro gastrointestinal digestion on their antioxidant activity, and the action of polyphenols from digested juices on proliferation, cell cycle and apoptosis in human colon cancer Caco-2 cells. The results showed that in vitro gastrointestinal digestion caused losses of some polyphenols, such as cyanidins derivatives from jaboticaba, possibly due to the exposure to conditions of intestinal pH. However, contents of free ellagic acid increased in all the juices analyzed, indicating the occurrence of hydrolysis during in vitro digestion process, releasing ellagic acid from the ellagitannins. The antioxidant activity was affected for different forms by the in vitro digestion, demonstrating be related to individual components present in each sample and the mechanisms by which they act as antioxidants. Regarding the evaluation of proliferation, cell-cycle and apoptosis, polyphenols from bioaccessible fractions of camu-camu showed about 30% of inhibition of proliferation, followed by cagaita with 24%, both at the highest concentration tested (50 &#181;g GAE/mL). Jaboticaba did not show inhibitory effect at the concentrations tested but the phenolic compounds of all bioaccessible fractions (50 &#181;g GAE/mL) showed arrest in G2/M phase of cell-cycle without inducing apoptosis in the Caco-2 cells. Results suggest that Myrtaceae polyphenols may modulate the proliferation of Caco-2 cells by blocking the progression of cell-cycle at G2/M phase, providing beneficial effects to gastrointestinal health.