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Potencial dos subprodutos da viticultura portuguesa como recursos naturais de compostos bioativos
| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 36694 | 4.79 MB | Adobe PDF |
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Abstract(s)
Vitis vinífera é a variedade de uva utilizada na produção de vinho e outros produtos, sendo cultivada por todo o mundo. No processo de produção de vinho muitos são os subprodutos da videira que são desperdiçados, entre eles as folhas, as sementes e os engaços. Estes subprodutos apresentam uma importante atividade biológica para a saúde. Estudos recentes demonstraram que várias são as partes da videira que tem na sua composição polifenóis, compostos que são benéficos para a saúde, dado que apresentam atividade antioxidante, antimicrobiana, anti-inflamatória, cardioprotetora, o que tem despertado cada vez mais interesse junto da comunidade científica. Dada a quantidade de vinho produzido a nível mundial, a quantidade destes subprodutos começa a ser um problema a nível ambiental, tornando-se assim urgente tomar medidas para a utilização destes para obter compostos bioativos com aplicações quer a nível da indústria farmacêutica, quer na medicina ou até a nível alimentar. Nesta dissertação avaliou-se a atividade antioxidante e antimicrobiana de extratos de grainhas e engaços de duas castas portuguesas, a Touriga Franca e a Touriga Nacional, obtidos com três solventes extratores, sendo eles, água, etanol e uma mistura hidroalcoólica. Foram avaliados o teor de compostos fenólicos totais e flavonoides totais presentes nos diferentes extratos, e ainda, a atividade antioxidante por espetrofotometria. Para avaliação da atividade antibacteriana (contra Staphylococcus aureus e Escherichia coli) e antifúngica (contra Candida albicans e Candida krusei) dos extratos recorremos ao Método de Microdiluição e determinação da Concentração Mínima Inibitória, usualmente utilizados na pesquisa de novos antimicrobianos. Por fim foi ainda avaliado o mecanismo de ação dos extratos no que respeita à capacidade de matar ou inibir o crescimento dos microrganismos à concentração máxima estudada. De um modo geral, a Touriga Nacional apresenta resultados mais promissores, desde o seu teor em compostos fenólicos e flavonoides à atividade antioxidante, e ainda na atividade antimicrobiana. Na atividade antimicrobiana as grainhas apresentam, de modo geral, melhores resultados que os engaços.
Vitis vinifera is a variety of grapes used in the production of wine and other products being cultivated throughout the whole world. In the wine production process, many subproducts are wasted, including leaves, seeds, and stalks. These subproducts have an important biological activity in terms of health. Recent studies have demonstrated that several parts of the vine have polyphenols in their composition, compounds that are beneficial to health, as they have antioxidant, antimicrobial, anti-inflammatory and cardioprotective activities, which has aroused increasing interest among the scientific community. Given the amount of wine produced worldwide, the amount of these subproducts it is beginning to be an environmental problem, making it urgent to take action and to use them to obtain bioactive compounds with applications both in the pharmaceutical industry and in medicine, or even at the food level. In this dissertation, it was evaluated the antioxidant and antimicrobial activity of extracts from seeds and stalks of two Portuguese grape varieties, Touriga Franca and Touriga Nacional, obtained with three extracting solvents, namely water, ethanol and a hydroalcoholic mixture. The content of total phenolic compounds and total flavonoids present in the different extracts were evaluated, as well as the antioxidant activity by spectrophotometry. To evaluate the antibacterial activity (against Staphylococcus aureus and Escherichia coli) and antifungal activity (against Candida albicans and Candida krusei) of the extracts, we used the Microdilution Method and determination of the Minimum Inhibitory Concentration, usually used in the search for new antimicrobials. Finally, the mechanism of action of the extracts was also evaluated regarding the ability to kill or inhibit the growth of microorganisms at the maximum concentration studied. In general, Touriga Nacional presents more promising results, from its content of phenolic compounds and flavonoids to its antioxidant activity, and its antimicrobial activity. In terms of antimicrobial activity, seeds generally present better results than stalks.
Vitis vinifera is a variety of grapes used in the production of wine and other products being cultivated throughout the whole world. In the wine production process, many subproducts are wasted, including leaves, seeds, and stalks. These subproducts have an important biological activity in terms of health. Recent studies have demonstrated that several parts of the vine have polyphenols in their composition, compounds that are beneficial to health, as they have antioxidant, antimicrobial, anti-inflammatory and cardioprotective activities, which has aroused increasing interest among the scientific community. Given the amount of wine produced worldwide, the amount of these subproducts it is beginning to be an environmental problem, making it urgent to take action and to use them to obtain bioactive compounds with applications both in the pharmaceutical industry and in medicine, or even at the food level. In this dissertation, it was evaluated the antioxidant and antimicrobial activity of extracts from seeds and stalks of two Portuguese grape varieties, Touriga Franca and Touriga Nacional, obtained with three extracting solvents, namely water, ethanol and a hydroalcoholic mixture. The content of total phenolic compounds and total flavonoids present in the different extracts were evaluated, as well as the antioxidant activity by spectrophotometry. To evaluate the antibacterial activity (against Staphylococcus aureus and Escherichia coli) and antifungal activity (against Candida albicans and Candida krusei) of the extracts, we used the Microdilution Method and determination of the Minimum Inhibitory Concentration, usually used in the search for new antimicrobials. Finally, the mechanism of action of the extracts was also evaluated regarding the ability to kill or inhibit the growth of microorganisms at the maximum concentration studied. In general, Touriga Nacional presents more promising results, from its content of phenolic compounds and flavonoids to its antioxidant activity, and its antimicrobial activity. In terms of antimicrobial activity, seeds generally present better results than stalks.
Description
Keywords
Subprodutos Vinha Antifúngicos Touriga Franca Touriga Nacional Antibacterianos Antioxidantes Compostos fenólicos Subproducts Vine Antifungals Antibacterials Antioxidants Phenolics compounds