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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Utilização da metodologia de superfície de resposta no desenvolvimento de um molho tipo Pesto visando a atividade antioxidante / Utilization of response surface methodology in the development of a Pesto sauce to maximize its antioxidant activity

Guilherme Afonso 06 September 2006 (has links)
Evidências recentes têm demonstrado que dietas com elevado conteúdo de vegetais, frutas e grãos podem reduzir o risco de diversas doenças não transmissíveis. As propriedades benéficas desses alimentos têm sido atribuídas, em grande parte, à presença de substâncias antioxidantes, que são capazes de diminuir os efeitos prejudiciais dos radicais livres. O objetivo deste trabalho foi desenvolver uma formulação de molho tipo Pesto, com base nas propriedades antioxidantes dos seus ingredientes principais: manjericão, castanha do Brasil e azeite de oliva extra virgem. A metodologia foi divida em duas fases: a primeira consistiu na avaliação da interação entre os componentes com atividade antioxidante (AA) presentes nos ingredientes principais do molho, realizada através da metodologia de superfície de resposta por modelagem de misturas. Foi utilizado um planejamento centróide simplex, no qual a resposta medida foi a atividade antioxidante dos extratos de diferentes polaridades obtidos das diferentes formulações. Utilizando-se o método DPPH (1,1-difenil-2-picrilhidrazil) e o sistema ß-caroteno/ácido linoléico, não foi encontrada interação entre os componentes com AA presentes nos ingredientes. Apesar dos modelos obtidos não descreverem adequadamente a variação dos resultados, o manjericão foi identificado como o ingrediente de maior contribuição para a AA total do molho. Foi realizada análise sensorial para determinar a formulação melhor aceita dentre as possibilidades obtidas. A segunda fase consistiu em submeter a formulação determinada na fase 1 às análises de composição centesimal, quantificação dos compostos fenólicos totais e quatro métodos in vitro de avaliação da AA: método do poder redutor, sistema ß-caroteno/ácido linoléico, DPPH e ensaio em meio lipídico pelo aparelho Rancimat®. A formulação final pode ser considerada como uma boa fonte de antioxidantes naturais e portanto fazer parte de uma dieta saudável. / Recent evidences have shown that high consumption of vegetables, fruits and grains can reduce the risk of non-communicable diseases. The healthy properties of these foods have been related mostly to the presence of antioxidants, substances which are known as capable of decreasing the harmful effects of free radicals. The objective of this work was to develop a Pesto sauce formulation, based on the antioxidant properties of its main ingredients: sweet basil, Brazil nut and extra-virgin olive oil. The methodology was divided in two phases: The first one consisted in the evaluation of the interaction between the components with antioxidant activity (AA) present in the sauce\'s main ingredients, applying the response surface methodology with a mixture model. A centroid simplex plan was used, in which the response measured was the AA of the extracts of different polarities from the different formulations. By using the DPPH (1,1-diphenyl-2-picryhydrazyl) method and the ß-carotene/linoleic acid system, no interaction between the components with AA was detected. Although the models could not describe properly the response variation, sweet basil was identified as the main responsible for the total AA of the sauce. Sensory analysis was conducted to determine the most accepted formulation among the possibilities. The second phase consisted in submitting the formulation obtained in phase 1 to centesimal composition analysis, quantification of total phenolics and four in vitro AA methods: reducing power, DPPH method, ß-carotene/linoleic acid system and the Rancimat® method. The final formulation may be considered a good source of natural antioxidants and therefore be part of a healthy diet.
322

Chemical characterization and biological activity of the Ceylon gooseberry (Dovyalis hebecarpa) in different ripening stages = Caracterização química e atividade biológica da groselha do ceilão (Ddovyalis hebecarpa) em diferentes estadios de maturação / Caracterização química e atividade biológica da groselha do ceilão (Dovyalis hebecarpa) em diferentes estadios de maturação

Bochi, Vivian Caetano, 1982- 23 August 2018 (has links)
Orientadores: Helena Teixeira Godoy, Elaine Conceição de Oliveira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-23T09:32:28Z (GMT). No. of bitstreams: 1 Bochi_VivianCaetano_D.pdf: 14853461 bytes, checksum: 20196ff92ca0c3039ebb5aded05718ad (MD5) Previous issue date: 2013 / Resumo: A groselha do Ceilão (Dovyalis hebecarpa) é uma fruta exótica de coloração roxa quando madura. Não foram encontrados trabalhos que identifiquem os principais compostos fenólicos na espécie, ação antioxidante e efeitos biológicos. Sendo assim, além da otimização da extração, esse trabalho avaliou os principais compostos fenólicos na casca e polpa de D. hebecarpa por cromatografia líquida acoplada a espectrômetro de massas (CLAE-DAD-EM), o potencial antioxidante in vitro e o efeito sobre a resposta imunológica em camundongos. Com exceção da razão entre amostra e solvente, avaliada univariadamente, a otimização das variáveis de extração foi realizada utilizando planejamento experimental multivariado. O processo otimizado foi realizado em menor tempo (20 minutos), com menos solvente orgânico (20% de acetona) e com maior rendimento (aumento de 10% no teor total de compostos fenólicos e de 26% no teor total de antocianinas monoméricas) do que a metodologia inicial. A caracterização do perfil de antocianinas revelou que D. hebecarpa é fonte de compostos não acilados, sendo delfinidina-3-O-rutinosídeo e cianidina-3-O-rutinosídeo os majoritários. Casca e polpa possuem composição similar, no entanto, maiores concentrações são encontradas na parte externa do fruto. Amostras de dois anos consecutivos e em duas datas de amostragem foram recolhidas para avaliação de variações entre estações do ano. Considerando que a ação antioxidante se dá por diversos mecanismos, metodologias de FRAP, ABTS e ORAC foram empregadas. Os maiores resultados de atividade antioxidante foram obtidos com a metodologia de ORAC, indicando marcada atividade sequestradora de radicais peroxil dos compostos extraídos. De forma diferenciada para polpa e casca dos frutos, efeitos significativos sob os teores de antocianinas, de compostos fenólicos e capacidade antioxidante, foram observados devido à variação climática entre as datas. Adicionalmente foram avaliados parâmetros biométricos e composição nutricional. Alterações no peso e tamanho dos frutos (p<0,05), assim como, na composição nutricional (p<0,05) foram observadas. Esses resultados, possivelmente, devem-se as diferenças de disponibilidade de água e incidência solar entre as datas de amostragem. Os valores médios dos teores de compostos fenólicos e antocianinas encontradas são similares aos relatados para outras frutas vermelhas. Nos testes in vivo, camundongos C57Black6 foram divididos em 4 grupos que receberam por 5 dias uma dose diária de extrato bruto em alta, média e baixa dosagem (32µg, 16µg e 8µg equivalentes de cianidina-3-O-glucosídeo/animal, respectivamente). Para o grupo controle foi utilizada solução salina. Após 24 horas do fim do tratamento, os animais foram imunizados com OVA (ovalbumina), conforme metodologia padrão. No 14° dia, os animais foram sacrificados e os tecidos recolhidos para análise. Foram monitoradas a proliferação celular em baço e linfonodos, assim como, sua diferenciação em linfócitos T CD4+/CD8+ por citometria de fluxo. Os grupos tratados com CGCE apresentaram redução na proliferação celular em linfonodos, assim como na razão CD4+/CD8+. Sendo assim, os resultados indicam um possível efeito anti-inflamatório do extrato aquoso bruto de groselha do Ceilão, porém pesquisas adicionais de caracterização de citocinas e tratamentos prolongados são necessárias para confirmação dos resultados encontrados / Abstract: D. hebecarpa is a dark purple/red berry produced in Brazil as an exotic fruit with potential for large scale production and commercialization. Fruits are believed to contain high phenolic and anthocyanin concentration that provide color and defense to the plant. Moreover, these compounds have been extensively studied for their antioxidant activity and potential human health benefits. Thus, this work has optimized extraction prior to the skin and pulp anthocyanin profile characterization by HPLC-PDA-MS aiming to obtain the simplest and mildest conditions with maximum phenolic yield. Moreover, it was evaluated in vitro antioxidant capacity and the effect of water-based crude extract on immune system of mice. Solid-liquid ratio was determined in a linear experiment using ANOVA and Tukey (p<0.05). Acetone, ethanol and water were the extraction solvents evaluated by Simplex Lattice design. Time and acid concentration were evaluated using response surface methodology (RSM) to determine variables effect and their interactions. The optimized conditions achieved were: solid-liquid ratio of 1:120, acetone 20% with 0.35% formic acid, 20min, and no re-extraction. However, satisfactory results were obtained using just water as solvent. The optimized extraction used less organic solvent than the other conditions tested and showed higher yields than the initial ones (an increase of 10% and 26% of total phenolic compounds and total monomeric anthocyanins, respectively). The analytical HPLC chromatogram showed five major anthocyanins (Delphinidin-3-glucoside, Delphinidin-3-rutinoside, Cyanidin-3-glucoside, Cyanidin-3-rutinoside, and Petunidin-3-rutinoside) in addition to two minor pigments (Peonidin-3-rutinoside and Malvidin-3-rutinoside). Samples from two consecutive years were used for quantification purposes and antioxidant measurements. High concentration of phenolics and anthocyanins were detected in skin samples with the same anthocyanin profile of pulp part. FRAP, ABTS, and ORAC methodologies were used to evaluate antioxidant mechanisms. A strong peroxyl scavenger capacity was detected for D.hebecarpa samples by ORAC methodology which could indicate possibly health effects of fruit consumption. Significant variations of anthocyanin, total phenolic content, and antioxidant capacity were observed in pulp and skim possibly as a result of weather conditions. Concomitantly, biometric parameters and nutritional composition seems to be affected as well (p<0.05). C57Black6 mice were used for in vivo evaluation of immuno-modulatory effect of water-based Ceylon gooseberry crude extract (CGCE). Animals were treated with high, medium, and low dosages of CGCE (32µg, 16µg, and 8µg cyanidin-3-O-glucose/animal/day, respectively) during 5 days. Saline solution was used as a control group. Animals were challenged after 24 hours from the last dose using a standardized immunization protocol with OVA and CFA. After euthanasia, blood, spleen, and lymph nodes were collected and analyzed. Cell proliferation using MTT and lymphocyte profile by flown citometry was determined in spleen and lymph nodes, as well as IgG levels in blood samples. Results indicate a possible anti-inflammatory effect. Since, there was an decrease in lymph node cell proliferation response as well as in CD4+/CD8+ ratio. In summary, D. hebecarpa is a rich source of anthocyanins with concentration levels as high as reported for other berry fruits. The strong antioxidant activity and some evidences of in vivo anti-inflammatory effects suggest this fruit as source for future scientific works aiming to evaluate possible health effects / Doutorado / Ciência de Alimentos / Doutora em Ciência de Alimentos
323

Análise de compostos fenólicos e avaliação da atividade antioxidante e antimicrobiana de extratos aquosos de cogumelos comestíveis produzidos no Brasil / Analysis of phenolic compounds and evaluation of antioxidant activity and antimicrobial of aqueous extracts of edible mushrooms produced in Brazil

Sousa, Jessica Maria Silva 19 August 2018 (has links)
Orientador: Helena Teixeira Godoy / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-19T16:32:45Z (GMT). No. of bitstreams: 1 Sousa_JessicaMariaSilva_M.pdf: 1636413 bytes, checksum: eef8c829695e9cc3aff1047919b3eaed (MD5) Previous issue date: 2012 / Resumo: O aprofundamento do estudo relativo aos compostos naturais com propriedades antioxidantes e antimicrobianas em cogumelos torna-se extremamente relevante tendo em vista a possibilidade de esses compostos serem empregados nas indústrias de alimentos, farmacêutica e de cosméticos. No entanto, não foram encontrados relatos sobre o perfil fenólico de cogumelos comestíveis produzidos no Brasil assim como também não foram encontrados trabalhos que utilizassem quatro ensaios diferentes para avaliar o potencial antioxidante dos cogumelos. Portanto, o objetivo desse trabalho foi avaliar o teor de compostos fenólicos e a capacidade antioxidante e antimicrobiana de 4 espécies de cogumelos comestíveis (A. bisporus, P. ostreatus, P. ostreatoroseus e L. edodes) produzidas no Brasil. Os compostos fenólicos totais (CFT) foram determinados pelo método de Folin-Cioacalteu e a identificação e quantificação individual dos fenólicos foi realizada por cromatografia líquida de alta eficiência (CLAE). A atividade antioxidante foi avaliada por quatro métodos: DPPH (2,2-difenil-1-picrilhidrazila), ABTS+¿ [2,2¿-azino-bis (3-etilbenzo-tiazolina-6-sulfonato)], FRAP (Ferric Reducing Antioxidant Power) e ORAC (Oxygen Radical Absorbance Capacity). O potencial antimicrobiano dos extratos foi avaliado através da concentração mínima inibitória (CIM). Todos os resultados obtidos para as diferentes análises foram analisados levando em consideração o período de colheita, os diferentes processamentos, graus de maturação e substratos de cultivo. No ensaio com o radical DPPH¿ o cogumelo que apresentou maior atividade antioxidante foi o Champignon de Paris (fresco). Já no ensaio com o radical ABTS+¿ e no ORAC os cogumelos que apresentaram maior ação antioxidante foram o Hiratake, o Shimeji (fresco), o Salmon e o Portobello. No ensaio FRAP o Portobello mostrou a maior atividade antioxidante. Os valores médios de CFT variaram entre 0,78 e 10,85 mg EAG/g de amostra liofilizada. Os cogumelos que apresentaram os maiores teores de CFT para o cultivo de verão e de inverno, respectivamente, foram o Hiratake com 10,09 mg EAG/g e 8,45 mg EAG/g, Salmon com 9,61 mg EAG/g e 9,45 mg EAG e Portobello com 9,07 mg EAG/g e 9,60 mg EAG. O processamento empregado ao cogumelo Champignon de Paris diminuiu consideravelmente o teor de CFT (de 7,04 mg EAG/g para 0,90 mg EAG/g - cultivo de verão) enquanto que no processo de secagem empregado ao cogumelo Shimeji não houve diminuição drástica no teor de CFT (de 8,83 mg EAG/g para 7,62 mg EAG/g - cultivo de verão). O grau de maturação influenciou no teor final de CFT mostrando que o Shimeji, colhido em estágio imaturo, possui menor teor de CFT (8,83 mg EAG/g ¿ cultivo de verão e 7,24 mg EAG/g ¿ cultivo de inverno) em comparação ao Hiratake, colhido em estágio mais maturo. Correlações positivas entre os resultados de CFT e os métodos de atividade antioxidante foram encontradas, e essa correlação foi maior para o ensaio com o radical livre ABTS¿+ e o ORAC (r = 0,92 e r = 0,89, respectivamente) do que para o ensaio FRAP (r = 0,45). Já entre o DPPH e os resultados de CFT foi encontrada baixa correlação negativa (r = -0,14). Dentre os compostos investigados por CLAE foram identificados e quantificados apenas os ácidos siríngico, p-cumárico e o trans-cinâmico, com predominância deste último. No ensaio antimicrobiano realizado verificou-se que o crescimento das leveduras C. albicans, C. rugosa, C. tropicalis, C. glabrata e C. utilis foi fortemente inibido pelos extratos aquosos dos cogumelos Shiitake (tora e composto), com CIMs variando entre 0,08 e 0,31 mg/mL. Estes resultados demonstram que os cogumelos comestíveis possuem grande potencial de utilização pela indústria farmacêutica e podem contribuir significativamente para uma boa condição de saúde devido à presença de antioxidantes / Abstract: The study of natural compounds with antioxidant and antimicrobial properties of mushrooms is extremely relevant to the use in the food, pharmaceutical and cosmetic industries. However, no reports were found about the phenolic profile of edible mushrooms produced in Brazil as well as were not found papers describing the use four different tests to evaluate the antioxidant potential of mushrooms. Therefore, the aim of this study is evaluate the phenolic content, antioxidant and antimicrobial activities of four species of edible mushrooms (A. bisporus, P. ostreatus, L. edodes and P. ostreatoroseus) produced in Brazil. The total phenolic compounds (TPC) were determined by Folin-Cioacalteu and the individual identification and quantification of phenolic compounds was performed by high performance liquid chromatography (HPLC). The antioxidant activity was evaluated by four methods: DPPH¿(2,2-diphenyl-1-picrylhydrazyl), ABTS+¿ [2,2 '-azino-bis (3-etilbenzo-thiazoline-6-sulfonate)], FRAP (Ferric Reducing antioxidant Power) and ORAC (Oxygen Radical Absorbance Capacity). The antimicrobial activity of extracts was evaluated by minimum inhibitory concentration (MIC). All the results obtained for the different analyzes were analyzed taking into account the period of harvesting, different processing, maturation degrees and cultivation substrates. In the assay with DPPH, the mushroom with the highest antioxidant activity was A. bisporus white (fresh). In the assays with the radical ABTS+¿ and ORAC, the mushrooms that showed the highest antioxidant activity were P. ostreatus (mature and fresh immature), P. ostreatoroseus and A. bisporus brown. In the FRAP assay the A. bisporus brown. showed the highest antioxidant activity. The average values of TPC ranged varied from 0.78 and 10.85 mg GAE/g lyophilized sample. The mushrooms with highest levels of TPC for the summer and winter cultivation, respectively, were P. ostreatus (mature) with 10.09 mg GAE/g and 8.45 mg GAE/g, P. ostreatoroseus with 9.61 mg GAE/g and 9, 45 mg GAE and A. bisporus brown with 9.07 mg GAE / g and 9.60 mg GAE. The processing used in the A. bisporus white has considerably reduced the content of TFC (from 7.04 mg GAE/g to 0.90 mg GAE/g - summer cultivation) while in the process of drying the mushroom used in the P. ostreatus (immature), no drastic decrease content of the TPC (from 8.83 mg of GAE/g to 7.62 mg GAE/g - summer cultivation). The maturation degree influenced the final content of the TPC showing P. ostreatus, harvested in an immature state, has a lower content of TPC (8.83 mg GAE/g - summer cultivation and 7.24 mg GAE/g - winter cultivation) compared to P. ostreatus, collected in more mature stage. Positive correlations between the results of TPC and methods of antioxidant activity were founded, and this correlation was higher for the test with free radical ABTS+¿ and ORAC (r = 0.92 and r = 0.89, respectively) than for the FRAP test (r = 0.45). Among the DPPH and the results of TFC was found low negative correlation (r = -0.14). Among the compounds investigated by HPLC were identified and quantified only the syringic, p-coumaric and trans-cinnamic acids, with predominance of the latter. In the assay antimicrobial it was found that the growth of yeasts C. albicans, C. rugosa, C. tropicalis, C. glabrata and C. utilis was strongly inhibited by aqueous extracts from the mushrooms Lentinula edodes (logs and compound), with MICs ranged varied from 0.08 to 0.31 mg / mL. These results demonstrate that edible mushrooms have great potential use by the pharmaceutical industry and can contribute significantly for a good health condition due to the presence of antioxidants / Mestrado / Ciência de Alimentos / Mestre em Ciência de Alimentos
324

Influência da interenxertia e dos sistemas de condução nas propriedades funcionais do pêssego.

Manica-Berto, Roberta 13 June 2008 (has links)
Made available in DSpace on 2014-08-20T13:42:04Z (GMT). No. of bitstreams: 1 Dissertacao_ Roberta_Manica_Berto.pdf: 606115 bytes, checksum: 445d0bdbfb17faf10be6cd11262a37f5 (MD5) Previous issue date: 2008-06-13 / The peach has in its composition bioactives compounds that can help in the retardation of aging and prevention of certain diseases. With the necessity to consider the existing interaction it among practices management and the functional attributes for, thus, getting significant advances in the referring studies the capacity antioxidant in the fruits, the objective of this work was to study the influence of the length interstock and diferent training systems in the functional properties on peaches, by an evaluation of its physicochemical and chemical characteristics.The experiments were carried out at Palma Agriculture Center (CAP/UFPel) during the 2007/08 growing season. In first experiment, was used peach tree orchard Jubileu‟ intergrafting with filters of Granada‟ with 0, 5, 10, 15 and 20 cm of length. In the laboratory, the effect of fruit parts (peel and flesh) for chemical variable was considered. In second experiment peach orchards Jubileu‟ and Eldorado‟ was used under diferent training systems on Capdeboscq rootstock. The treatments had been: cultivate - Jubileu and Eldorado, training systems - vase, central leader and y fruit parts (peel and flesh). In both experiments physicochemicals variables evaluated: average weight fruits, classification, peel color (L*, a*, b* and h°), flesh firmness, SST, ATT, pH and SST/ATT. Chemicals variables evaluated: antioxidant activity, total carotenoids, L-ascorbic acid and total phenols. In general, the interstock, independently of the length of filters, did not affect the physicochemical and chemicals characteristics. However, the training systems had influenced, directly, physicochemical characteristics in peaches Jubileu‟ and Eldorado‟. Specifically, peaches Eldorado‟ trained as an Y concentrated, in the peel, greater increasing total carotenoids. / O pêssego possui em sua composição compostos bioativos que podem agir no retardo do envelhecimento e na prevenção de certas doenças. Tendo em vista a necessidade de considerar a interação existente entre as práticas de manejo e os atributos funcionais para, assim, obter avanços significativos nos estudos referentes a teores de antioxidantes nas frutas, esse trabalho teve como objetivo estudar a influência do comprimento do interenxerto e dos diferentes sistemas de condução nas propriedades funcionais de pêssego, através da avaliação de suas características físico-químicas e químicas. Para isso, foram conduzidos dois experimentos na safra 2007/08, no Centro Agropecuário da Palma (CAP/UFPel). No primeiro experimento, foi utilizado pomar de pessegueiro Jubileu‟ interenxertado com filtros da cultivar Granada com 5, 10, 15 e 20 cm de comprimento, além de testemunha (sem filtro). No laboratório, além dessas variáveis, foi considerado o efeito de partes do fruto (casca e polpa) para a caracterização química. No segundo experimento foram utilizados pomares de pessegueiros Jubileu‟ e Eldorado‟ com diferentes sistemas de condução, enxertados sobre o porta-enxerto Capdeboscq. Os tratamentos resultaram da interação cultivares - Jubileu e Eldorado, sistemas de condução - Vaso, Líder Central e Y e partes do fruto (casca e polpa). Em ambos os experimentos as variáveis físico-químicas avaliadas foram: peso médio das frutas, classificação, cor da epiderme (L*, a*, b* e h°), firmeza de polpa, SST, ATT, pH e SST/ATT. As variáveis químicas foram: atividade antioxidante, carotenóides totais, ácido L-ascórbico e fenóis totais. Em geral, constatou-se que o emprego da interenxertia, independentemente do comprimento do interenxerto, não afetou as características físico-químicas e químicas em pêssegos Jubileu‟, entretanto os sistemas de condução influenciaram diretamente as características físico-químicas de Jubileu‟ e Eldorado‟. Especificamente, pêssegos Eldorado‟ conduzidos em Y concentraram, na casca, elevados teores de carotenóides totais.
325

Caracterização físico-química e fitoquímica de pêssegos da cv. Maciel sobre diferentes porta-enxertos / Physico-chemical and phytochemical characteristic in peaches of cv. Maciel about different roostocks

Betemps, Débora Leitzke 29 March 2010 (has links)
Made available in DSpace on 2014-08-20T14:22:07Z (GMT). No. of bitstreams: 1 Dissertacao_Debora_Leitzke_Betemps.pdf: 1110781 bytes, checksum: 2e516a9e01a150ed3520ffe92559384d (MD5) Previous issue date: 2010-03-29 / Althought there are researches that report the influence of rootstock about the scion cultivar, changing their behavior in relation to development, productivity, resistance, nutrition, maturation time and the quality of the fruits, these results are not conclusive. Objective of the study was evaluate the effect of rootstock Aldrighi, Capdeboscq, Flordaguard, Nemaguard, Okinawa and Umezeiro about quality of peaches cultivar Maciel. The fruits of the cultivar Maciel are from two orchards located in the Agricultural Center of Palma UFPel/Capão do Leão and in the experimental Estation of the Federal University of Rio Grande do Sul UFRGS/Eldorado do Sul. After the harvest, the fruits carried the following Physico-chemical analysis: acidity, skin color, total soluble solids, pH, 'Ratio' and firmness. For phytochemical analysis, fruits were separated into peel and flesh, stored in ultra-freezer, and later held the analysis of individual and total phenols, total and individual carotenoids and antioxidant activity. For Palma‟s fruits, the rootstock evaluated influenced considerably the acidity parameters, firmness, color of coating, pH, and ratio. These effects were not observed in the experimental Estation UFRGS with the same cultivar. The values of phenols and carotenoids total and individual were influenced by the rootstocks both the flesh and the peel, for the two localities. The Okinawa‟ had the highest average of total phenols in the peel for both places, Flordaguard‟ the flesh showed the highest average for the CAP‟s fruit and Nemaguard‟ to the fruits EE/UFRGS. The quantification of phenolic compounds, the gallic acid is the highest expression followed by p-hydroxybenzoic, p-coumaric and caffeic. For carotenoids in the flesh Okinawa‟ showed the highest average not differing from Aldrighi‟ while in the largest EE/UFRGS results were found in the Capdeboscq‟, Nemaguard‟ and Umezeiro‟. For carotenoids, β-cryptoxanthin, is the majority pigment, still presenting licopen and β-caroten in minors amounts. Nemaguard, Aldrighi and Umezeiro‟ present a higher value for antioxidant capacity. In the analysis of correlation between phytochemical were watched a weak and positive correlation for the flesh of the fruits and for the peel a correlation weak and negative. It is conclude that the rootstock might affect in an undirected form some phytochemical and physico-chemical, for both localities in which fruits were characterized. / Embora existam pesquisas que relatem a influência do porta-enxerto sobre a cultivar copa, alterando o seu comportamento em relação ao desenvolvimento, produtividade, resistência, nutrição, época de maturação e qualidade dos frutos, os resultados ainda não são conclusivos. Objetivou-se com o trabalho avaliar o efeito dos porta-enxertos Aldrighi, Capdeboscq, Flordaguard, Nemaguard, Okinawa e umezeiro sobre a qualidade de pêssegos da cultivar Maciel. Os frutos foram provenientes da safra de 2008 de dois pomares, sendo um localizado no Centro Agropecuário da Palma UFPel/Capão do Leão (CAP/UFPel) e outro na Estação Experimental da Universidade Federal do Rio Grande do Sul UFRGS/Eldorado do Sul (EE/UFRGS). Após a colheita dos frutos procederam-se as seguintes análises físico-químicas: acidez (AT), coloração da epiderme, sólidos solúveis totais (SST), pH, relação SST/AT e firmeza de polpa. Para as análises fitoquímicas os frutos foram separados em casca e polpa e armazenados em ultra-freezer e posteriormente realizou-se a análise de fenóis totais e individuais, carotenóides totais e individuais e atividade antioxidante. Para os frutos provenientes do CAP/UFPel, os porta-enxertos avaliados influenciaram significativamente a acidez, firmeza, cor de recobrimento, pH e ratio. Estes efeitos não foram observados com os frutos provenientes da EE/ UFRGS com esta mesma cultivar onde somente a firmeza apresentou efeito significante dos porta-enxertos. Os valores de fenóis e carotenóides totais e individuais foram influenciados pelos porta-enxertos tanto na polpa quanto na casca, para as duas localidades.O Okinawa‟ obteve as maiores médias de fenóis totais na casca para as duas localidades, na polpa Flordaguard‟ apresentou as maiores médias para os frutos do CAP/UFPel e Nemaguard‟ para os frutos da EE/UFPel. Na quantificação de compostos fenólicos, o ácido gálico foi o de maior expressão seguido dos ácidos hidroxibenzóico, cumárico e cafeíco. Para carotenóides totais, na polpa, Okinawa‟ e Aldrighi‟ apresentaram as maiores médias não diferindo entre si no CAP/UFPel enquanto que na EE/UFRGS os maiores resultados foram quantificados em Capdeboscq‟, Nemaguard‟ e Umezeiro‟. Na quantificação dos carotenóides individuais, o β-criptoxantina é o pigmento majoritário apresentando ainda licopeno e β-caroteno em quantidades menores. Nemaguard, Aldrighi e Umezeiro‟ apresentaram maiores valores para capacidade antioxidante para a polpa dos frutos do CAP/UFPel sendo que Nemaguard‟ e Aldrighi‟ mantiveram este resultado para polpa da EE/UFRGS. Na análise de correlação entre os fitoquímicos, observou-se uma correlação fraca e positiva para a polpa dos frutos e para casca uma correlação fraca e negativa. Conclui-se que o porta-enxerto pode afetar de forma indireta alguns parâmetros físico-químicos e fitoquímicos, para as duas localidades na qual os frutos foram caracterizados.
326

Activité anti-oxydante, et caractérisation phénolique du fruit de palmier amazonien Oenocarpus bataua (patawa)

Rezaire, Aïra 19 December 2012 (has links)
En raison de sa richesse en ressources génétiques, et des utilisations traditionnelles locales qui en sont faites, la biodiversité végétale issue du bassin amazonien constitue une véritable source de principes actifs à valoriser. L’espèce Euterpe oleracea Mart., vernaculairement appelée baie d’açai, qui connaît un intérêt scientifique important, est le parfait exemple de ressources naturelles bioactives valorisées issues de cette zone géographique. Les études scientifiques lui confèrent de très nombreuses propriétés biologiques, mais, la plus connue et la plus médiatisée est sa capacité antioxydante liée majoritairement à sa composition polyphénolique. En Guyane française, on peut parler de « diversité » au sein de la famille des Palmiers puisque plus de 75 espèces y ont été recensées. Parmi lesquelles, on peut citer une espèce très commune ayant des propriétés surtout alimentaires, et dont la connaissance phytochimique reste, à l’heure actuelle, très limitée : l’Oenocarpus bataua Mart dit patawa. Ce sujet de thèse de doctorat s’articule autour de la mesure de l’activité antioxydante du fruit mûr de ce palmier, et de la détermination des polyphénols responsables de cette dernière. La singularité de ce travail réside dans l’étude des différentes composantes tissulaires du fruit : mésocarpe, épicarpe et mélange épicarpe/mésocarpe (MEM). Dans un premier temps, les conditions les plus favorables d’extraction de biomolécules (notamment de l’épicarpe et du mésocarpe) ont été définies à l’aide du test DPPH. Les tests préliminaires effectués sur les tissus pris séparément, ont conduit à sélectionner un mélange acétone/eau (70/30, v/v) pour révéler, au mieux, la capacité antioxydante de chaque partie du fruit. Une étape de délipidation initiale s’est avérée nécessaire dans le cas de l’étude du mésocarpe. La confirmation de l’activité antioxydante a été réalisée au moyen d’autres tests d’activité chimique (TEAC, FRAP, ORAC), et a été complétée par l’utilisation d’un test d’activité biologique (KRL) en raison de ses mécanismes réactionnels plus complets. Il en ressort que le tissu végétal le plus antioxydant est le mésocarpe qui contient des proanthocyanidines, famille de composés phénoliques connue pour ses nombreuses activités biologiques.Le même travail a été effectué sur les tissus regroupés (fruit global ou MEM). Ainsi, a été retenue l’utilisation du solvant mixte acétone/eau sans étape de délipidation initiale. La capacité antioxydante du fruit étudié a été comparée à celle de l’açai, espèce choisie comme référence. Il s’avère que les extraits d’açai ont une activité antioxydante très supérieure à celle du patawa lorsqu’ils sont testés vis-à-vis de l’ORAC et du KRL. Le tissu mésocarpe a, lui, démontré une capacité antioxydante supérieure à celle de l’açai. Ces résultats sont à associer avec la composition phytochimique propre à chaque fruit. La composition polyphénolique du fruit de patawa, déterminée par UPLC/MSn, supposerait la présence d’anthocyanes, de tanins condensés, de stilbènes et d’acides phénoliques. Ces travaux, qui méritent d’être approfondis, en particulier pour le mésocarpe, ouvrent de nouvelles perspectives d’utilisation du fruit patawa, en particulier l’incorporation de composés phénoliques issus du mésocarpe dans des formulations galéniques ayant attrait aux domaines de la Nutrition, de la Cosmétique et de la Pharmaceutique. / Due to its wealth in genetic resources, and to traditional uses, plant biodiversity issued from the Amazonian Basin is a real source of active process to valorize. The specie Euterpeoleracea Mart., usually called acai berry, which is experiencing a huge scientific interest, is the perfect example of valued natural bioactive resources from the geographic area. Scientific studies give it many biological properties, but the most known is its antioxidant property mainly due to its polyphenolic composition. In French Guiana, we can use the term “diversity” within the palm family with more than 75 species identified. Among them is a common species, Oenocarpus bataua Mart., called “Patawa”, mainly with alimentary properties but for which knowledge of phytochemical properties is until now very poor. The present research deals with determining the antioxidant activity of this palm fruit and with the identification of the polyphenols responsible for it.The uniqueness of this work lays in the study of the different tissue components of this fruit namely the mesocarp, the epicarp and mixing epicarp / mesocarp (MEM). In a first time, the most favorable extraction conditions of biomolecules (particularly of the epicarp and mesocarp) were defined using the DPPH test. The preliminary tests performed on those tissues taken separately, have led to select an acetone / water (70/30, v / v) to reveal, at best, the antioxidant capacity of each part of the fruit. An initial defatting step was necessary in the case of the study of the mesocarp. The confirmation of the antioxidant activity was carried out by other tests of chemical activity (TEAC, FRAP, ORAC), and was supplemented by the use of a bioassay (KRL) due to its more complete reaction mechanisms. Results point out that the most antioxidant tissue is the mesocarp that contains proanthocyanidins, phenolics of a chemical family known for its numerous biological activities.The same work was performed on tissues combined (overall result). The mixed solvent acetone / water, without initial defatting step, has been selected. The antioxidant capacity of fruit was compared to that of the Acai specie chosen as a reference. It turns out that acai extracts have antioxidant activity much greater than that of Patawa when tested vis-à-vis of ORAC and KRL. In contrary, mesocarp tissue has a greater antioxidant capacity than that of Acai. These results can be associated with the phytochemical composition of each fruit. The polyphenolic composition of the fruit of Patawa determined by UPLC / MSn, reflects the presence of anthocyanins, condensed tannins, stilbene and phenolic acids. This work, which deserves to be deepened, especially for the mesocarp tissue, opens new prospects for the use of Patawa fruit, especially the incorporation of phenolic compounds from the mesocarp in pharmaceutical formulations linked to the fields of Nutrition, of Cosmetics and Pharmaceuticals.
327

Determination of the in vitro antidiabetic potential of a polyherbal commercial tea

Paddy, Veronica January 2014 (has links)
Type 2 diabetes mellitus (T2DM) is an increasing global health concern, currently affecting an estimated 382 million individuals. There is no cure for T2DM and the search for new and improved treatments is ongoing. Presently, various pharmacological regimens are available to treat T2DM, but with varied success. Thousands of traditional herbs are also used to treat T2DM, but mainly without scientific validation. The aim of this study was to assess the polyphenolic content, antioxidant capacity, as well as in vitro toxicity and hypoglycaemic activity of a commercial ‘antidiabetic’ tea mixture (Diabetea) and its individual constituents: Achillea millefolium L. (Yarrow), Agathosma betulina Bartl. & Wendl. (Buchu), Salvia officinalis L. (Sage), Taraxacum officinalis L. (Dandelion), Thymus vulgaris L. (Thyme), Trigonella foenum-graecum L. (Fenugreek) and Urtica urens L. (Nettle). All herbs were tested as crude extracts, prepared using hot water (HW) and dichloromethane (DCM). The total polyphenolic content of each extract was determined using the Folin-Ciocalteau and aluminium trichloride methods. The non-cellular antioxidant activity was assessed using 2,2-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) methods. The cell-based antioxidant activity was measured against p-chloranil-induced generation of reactive oxygen species (ROS) in Ea.hy926 cells, using the fluorescent dye, 2',7'-dichlorfluorescein-diacetate (DCFH-DA). The effect of each extract on the viability of C2C12 myotubes, Ea.hy926 endothelial cells and human lymphocytes (HL) was determined using sulforhodamine B (SRB). The in vitro hypoglycaemic activity was assessed against α-amylase and α-glucosidase activity using 3,5-dinitrosalicylic acid (DNSA) and p-nitrophenyl-α-D-glucopyranoside (p-NPG), respectively. The type of inhibition exerted on these enzymes was determined using the Michaelis-Menten enzyme kinetics model, expressed as mixed, competitive, non-competitive and uncompetitive. Glucose uptake activity was measured using the 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino]-2-deoxy-D-glucose (2-NBDG) fluorescent analogue. T. vulgaris and S. officinalis had the highest amount of polyphenols of all extracts tested. The HW extracts of T. vulgaris and S. officinalis showed significant (p < 0.05) cell-free antioxidant activity and cell-based radical scavenging activity. In addition, U. urens (HW) also limited cell-based ROS generation (p < 0.05). The Diabetea extracts presented with poor antioxidant activities, of which some had a pro-oxidant effect on Ea.hy926 cells. The positive linear relationship between antioxidant activity and polyphenolic content was shown to be dependent on the solvent type used. All of the DCM extracts had low antioxidant activity and polyphenolic content. None of the extracts produced < 50% cell density at the concentrations tested (1.3 - 20 μg/mℓ). In general, the DCM extracts showed a greater decrease in cell density than the HW extracts. The Ea.hy926 cells were the least affected by the extracts in terms of decreased cell density. The DCM extract of U. urens inhibited α-amylase activity in a mixed manner, which was comparable to the percentage inhibition exerted by the commercial drug, acarbose. Both the HW and DCM extracts of U. urens caused a significant (p < 0.05) increase in glucose uptake into C2C12 myotubes. The HW extract of T. vulgaris had a significant (p < 0.05) inhibitory activity against α-glucosidase (mixed). It also caused the uptake of glucose into C2C12 myotubes, which was significantly (p <0.05) more active than insulin. S. officinalis (DCM extract) also inhibited α-glucosidase activity (p < 0.05) in a mixed manner. Its HW extract displayed potent hypoglycaemic potential by causing glucose uptake into C2C12 myotubes, which was more significant (p < 0.05) than the activity of the positive control, insulin. The DCM extract of A. betulina was active against α-glucosidase (non-competitive), which was comparable to the activity of acarbose. Its HW extract also showed a significant (p < 0.05) glucose uptake activity. Furthermore, the DCM extracts of T. officinalis, A. millefolium, Diabetea and HW extracts of T. foenum-graecum and T. officinalis also caused a significant (p < 0.05) increase in glucose uptake into C2C12 myotubes. This study provides evidence for the antidiabetic potential of T. vulgaris and S. officianlis, in terms of antioxidant capacity and potential to prevent of post-prandial hyperglycaemia and alleviate hyperglycaemia by mimicking the action of insulin. In addition, the organic preparation of U. urens is also a potent α-amylase inhibitor. All herbs tested in this study exerted some form of in vitro antidiabetic activity. The Diabetea mixture, as a traditional preparation, did not have a significant antidiabetic capacity. In vitro observations from this study do not support the use of Diabetea as an antidiabetic preparation and reveal that some of the individual extracts prove more efficacious than the herb mixture. / Dissertation (MSc)--University of Pretoria, 2014. / lk2014 / Pharmacology / MSc / Unrestricted
328

3-Deoxyanthocyanins : Chemical synthesis, structural transformations, affinity for metal ions and serum albumin, antioxidant activity / 3-Deoxyanthocyanes : Synthèse chimique, transformations structurales, affinité pour les ions métalliques et l'albumine de sérum, activité antioxydante

Al Bittar, Sheiraz 17 June 2016 (has links)
Ce travail porte sur la synthèse chimique d’analogues simples d’anthocyanes, une classe majeure de pigments naturels solubles dans l’eau. Onze ions flavylium substitués par des groupements hydroxyl,méthoxyl et beta-D-glucopyranosyloxyl en positions 4’, 5 et 7 ont été préparés en utilisant des procédures simples. De plus, les deux principales 3-désoxyanthocyanidines du sorgho rouge, l’apigéninidine (APN) et la lutéolinidine (LTN), ont été synthétisées en une seule étape. Les propriétés physico-chimiques ainsi que l’activité antioxydante ont été étudiées pour le chlorure de 3’,4’,7-trihydroxyflavylium (P1), son 7-O-beta-D-glucoside (P2) et le chlorure de 3’,4’,5,7-tétrahydroxyflavylium (LTN). Grâce à leur noyau catéchol, ces pigments complexent rapidement FeIII, AlIII and CuI et ne se lient que faiblement à FeII tout en stimulant son autoxydation en FeIII. Suite à la complexation de CuII, les pigments subissent une oxydation. Les aglycones P1 et LTN sont des ligands modérés de l’albumine de sérum humain (HSA) et leurs chalcones ont montré une plus grande affinité pour la HSA que leurs formes colorées. Leur capacité antioxydante a été démontrée par le test de réduction du radical stable DPPH et par l’inhibition de la peroxydation lipidique induite par le fer héminique, un modèle de stress oxydant postprandial dans l’estomac. Les aglycones P1 et LTN (particulièrement, dans leur forme incolore chalcone) sont plus efficaces que le glucoside P2. / This work deals with the chemical synthesis of simple analogs of anthocyanins, the main class of watersolublenatural pigments. Eleven flavylium ions with hydroxyl, methoxyl and beta-D-glucopyranosyloxylsubstituents at positions 4’, 5 and 7 have been prepared by straightforward chemical procedures.Moreover, the two main 3-deoxyanthocyanidins of red sorghum, apigeninidin (APN) and luteolinidin(LTN), have been synthesized in a one-step protocol. The physicochemical properties and antioxidantactivity are investigated for 3’,4’,7-trihydroxyflavylium chloride (P1), its 7-O-beta-D-glucoside (P2) and3’,4’,5,7-tetrahydroxyflavylium chloride (LTN). Owing to their catechol B-ring, they rapidly bind FeIII,AlIII and CuI, more weakly interact with FeII while promoting its autoxidation to FeIII. Following CuIIbinding, the pigments undergo oxidation. Aglycones P1 and LTN are moderate ligands of human serumalbumin (HSA) with chalcones having a higher affinity for HSA than the corresponding colored forms.The antioxidant activity of P1, P2 and LTN is investigated via two tests: reduction of the stable DPPHradical and inhibition of heme-induced lipid peroxidation (a model of postprandial oxidative stress inthe stomach). Aglycones P1 and LTN (especially in their colorless chalcone form) are more potent thanglucoside P2.
329

Extraction, identification, caractérisation des activités biologiques de flavonoïdes de Nitraria retusa et synthèse de dérivés acylés de ces molécules par voie enzymatique / Extraction, identification, characterization of biological activities of Nitraria retusa flavonoids and enzymatic synthesis of acylated derivatives of these molecules

Hadj Salem, Jamila 09 October 2009 (has links)
Ce travail a consisté, dans un premier temps, à extraire et à identifier les flavonoïdes majeurs contenus dans les feuilles de Nitraria retusa et à évaluer leurs activités biologiques. Quatre flavonoïdes ont été identifiés dans les extraits et les fractions obtenus : l’isorhamnétine, l’isorhamnétine-3-O-glucoside et les deux isomères isorhamnétine-3-O-rutinoside et isorhamnétine-3-O-robinobioside. L’étude des activités biologiques des extraits et des fractions de N. retusa a permis d’établir une relation linéaire entre leur teneur en flavonoïdes et leurs activités antioxydantes et antiprolifératives, les milieux les plus riches présentant les activités les plus importantes. Ces activités dépendent également de la nature des flavonoïdes présents ; ainsi, la très forte activité d’inhibition de la xanthine oxydase relevée pour la fraction au chloroforme et sa grande capacité à piéger le radical DPPH ont été attribuées à sa teneur élevée en isorhamnétine, flavonoïde aglycone présentant une grande analogie structurale avec la quercétine, molécule bien connue pour ses activités antioxydantes. Dans un deuxième temps, l’acylation enzymatique de l’isoquercitrine, flavonoïde modèle, et de l’isorhamnétine-3-O-glucoside a été étudiée pour tenter d’améliorer leurs propriétés. L’acylation enzymatique de l’isoquercitrine par des esters éthyliques d’acides gras de différentes longueurs de chaîne, catalysée par la lipase B de Candida antarctica, a montré que les performances de la réaction sont inversement proportionnelles à la longueur de la chaîne du donneur d’acyle. Des résultats similaires ont été obtenus lors de l’acylation de l’isorhamnétine-3-O-glucoside. Les activités des esters d’isoquercitrine et d’isorhamnétine-3-O-glucoside ont été évaluées et comparées à celles des flavonoïdes non acylés. Les esters ont montré des activités antiprolifératives vis-à-vis de cellules Caco2 et d’inhibition de la xanthine oxydase plus importantes que celles des molécules d’origine. Finalement, ce travail a permis d’apporter des éléments de compréhension de la relation structure-activité de flavonoïdes et de leurs dérivés acylés / The present work firstly consisted in studying the extraction and the identification of major flavonoids contained in Nitraria retusa leaves and evaluating their biological activities. Four flavonoids were identified in extracts and fractions: isorhamnetin, isorhamnetin-3-O-glucoside and the two isomers isorhamnetin-3-O-rutinoside and isorhamnetin-3-O-robinobioside. The evaluation of the biological activities of extracts and fractions of N. retusa allowed to establish a linear relationship between their antioxidant and antiproliferative activities and their total flavonoids content, the most enriched exhibiting the highest activities. The nature of the flavonoids present in the extracts and fractions was shown to be important too. Thus, the strong xanthine oxidase inhibition activity and the high DPPH radical scavenging capacity observed for the chloroform fraction can be attributed to its high content in the aglycone flavonoid isorhamnetin, a structural analogue of quercetin which is well known for its antioxidant activities. In a second part, the enzymatic acylation of isoquercitrin as a model compound and isorhamnetin-3-O-glucoside was studied in order to improve their properties. The enzymatic acylation of isoquercitrin by fatty acid ethyl esters of different chain lengths, catalyzed by the lipase B of Candida antarctica, showed that the performance of the reaction is inversely proportional to the acyl donor chain length. Similar results were obtained when acylating the isorhamnetin-3-O-glucoside. The activities of isoquercitrin and isorhamnetin-3-O-glucoside esters were determined and compared to that of initial flavonoids. Esters exhibited higher antiproliferative towards Caco2 cells and xanthine oxidase inhibition activities than original compounds. Finally, this work led to a better understanding of the structure-activity relationship of flavonoids and their acylated derivatives
330

Compostos bioativos em óleos e resíduos de sementes de uvas orgânicas e convencionais

Assumpção, Carolina Fagundes January 2014 (has links)
A indústria de alimentos é responsável pela produção de grandes quantidades de resíduos que podem representar altos custos quando não utilizados. Entre estes resíduos estão as sementes oriundas do processamento de uva, uma das frutas mais consumidas no mundo. Além do aproveitamento de resíduos e consequentemente novas formas de consumo, este material tem sido relatado como fonte natural rica em compostos bioativos. Neste contexto, o consumo de alimentos mais saudáveis também tem impulsionado a busca e a preferência por alimentos orgânicos. Assim, para investigar o potencial de utilização de resíduo da indústria de processamento de suco de uva (Vitis labrusca, cv. “Bordô” e “Isabel”) foi analisado o resíduo da obtenção do óleo de sementes de uvas orgânicas e convencionais quanto ao teor de carotenoides e atividade antioxidante em comparação à semente integral. Os resíduos orgânicos e convencionais apresentaram os maiores teores de carotenoides totais, pró-vitamina A e atividade antioxidante por DPPH em relação a semente integral. O resíduo convencional destacou-se pela maior atividade antioxidante por TRAP e pelos teores mais significativos de carotenoides presentes no extrato antioxidante. também foram determinados O conteúdo de compostos bioativos e a estabilidade oxidativa dos óleos obtidos da prensagem das sementes orgânicas e convencionais Bordô e Isabel. Não foi observada diferença significativa entre as amostras quanto à atividade antioxidante por TRAP, porém os óleos Bordôs apresentaram-se mais estáveis ao aquecimento, com teores mais significativos de luteína, α e β-caroteno e α-tocoferol. A fim de investigar a qualidade, estabilidade oxidativa e conteúdo de compostos bioativos nestes óleos, foi realizado o refino do óleo Bordô orgânico. Não foi observada presença de β-caroteno e zeaxantina no óleo refinado e o óleo virgem de mesmo cultivar apresentou maior estabilidade ao aquecimento. Neste contexto, os resultados sugerem o consumo de óleos virgens devido a presença e maior quantidade de compostos bioativos. Não foi observada diferença significativa entre os diferentes modos de cultivo, sugerindo que a preferência por alimentos orgânicos pode restringir-se à motivos como ausência de agrotóxicos e apelo socioambiental. Os resíduos obtidos do processamento de uva, inclusive da obtenção do óleo destacaram-se pela alta atividade antioxidante e quantidade significativa de carotenoides, o que sugere sua inserção na alimentação como fonte natural rica em compostos bioativos. / The food industry is responsible for producing large quantities of waste that may represent high costs when not used. Some of these residues are the seeds derived from the processing of grapes, one of the most consumed fruits worldwide. In addition to the reuse of waste and consequently new forms of consumption, this material has been reported to be rich natural source of bioactive compounds. In this context, the consumption of healthier foods has also driven the search and preference for organic foods. Therefore, to investigate the potential use of grape processing waste (Vitis labrusca, variety “Bordô” and “Isabel”), the residues obtained from the extraction of oil from organic and conventional grape seeds were examined to determine their content of carotenoids and antioxidant activity compared with those found in the whole seed. The organic and conventional residues exhibited higher levels of total carotenoids, provitamin A, and antioxidant activity by DPPH compared with the corresponding whole seeds. The conventional residue presented the highest antioxidant activity by TRAP and the highest levels of carotenoids in the antioxidant extract. The content of bioactive compounds and the oxidative stability of the oils obtained from the pressing of organic and conventional seeds “Bordô” and “Isabel” were also determined. No significant difference in the antioxidant activity by TRAP was observed between the samples, but the “Bordô” oils were more stable when heated and exhibited higher levels of lutein, α and β-carotene, and α-tocopherol. To investigate the quality, oxidative stability, and content of bioactive compounds in these oils, the organic “Bordô” oil was refined. The refined oil did not contain β-carotene and zeaxanthin, and the virgin oil of the same variety showed greater stability to heating. Thus, the results recommend the consumption of virgin oils due to their larger content of bioactive compounds. No significant difference was observed between the different modes of cultivation, suggesting that the preference for organic foods can be restricted to reasons such as the absence of pesticides and environmental appeal. The residues obtained from grape processing, including the residues obtained from the extraction of oil, exhibited high antioxidant activity and a high amount of carotenoids, suggesting their inclusion in foods as a natural source rich in bioactive compounds.

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