Baoshan Sun¹, M. Isabel Spranger¹

¹Estação Vitivinícola Nacional, Instituto Nacional de Investigação Agrária e das Pescas, 2565-191 Dois Portos, Portugal. E-mail: inia.evn.quim@oninet.pt

(Manuscrito recebido em 16.09.05. Aceite para publicação em 14.11.05.)

SUMMARY

From the point of view of biological importance, proanthocyanidins (condensed tannins) and stilbenes (1,2-diarylethenes) are the two most important classes of polyphenols in grape and wine, which have attracted considerable attention of the international scientific community during the last fifteen years, due essentially to their potential beneficial health effects, related to their protective action towards cardiovascular disease and the oxygen free radical scavenger capacity. Numerous research works on proanthocyanidins and stilbenes have been published, but the majority of them have focused on the structural identification and biological activities of these compounds. Furthermore, less attention has been paid on their quantitative aspects and few analytical methods have been validated. This paper introduces briefly grape and wine proanthocyanidins and stilbenes and presents some works realized in our laboratory concerning quantitative extraction and analysis of these compounds.

RESUMO

Revisão: extracção e análise quantitativa de proantocianidinas e estilbenos da uva e do vinho

Do ponto de vista de importância biológica, as proantocianidinas (taninos condensados) e os estilbenos (1,2-diarilletenos) são as duas classes de polifenóis mais importantes na uva e no vinho, o que tem chamado a muito atenção da comunidade científica internacional durante os últimos 15 anos, devido essencialmente aos potenciais efeitos benéficos destes compostos para a saúde humana, relativamente à sua acção protectiva contra a doença cardiovascular e a sua capacidade de captar radicais livres de oxigénio. Numerosos trabalhos de investigação sobre as proantocianidinas e os estilbenos foram publicados, mas a maior parte deles têm incidido na identificação estrutural e nas actividades biológicas destes compostos. Porém, pouca atenção tem sido dispensada aos aspectos quantitativos e poucos métodos analíticos têm sido validados. Este artigo apresenta uma breve introdução sobre as proantocianidinas e os estilbenos da uva e do vinho e trabalhos realizados no nosso laboratório relativamente à extracção e análise quantitativa destes compostos.

Palavras chave: uva, vinho, proantocianidinas, estibenos, extracção, análise.

RÉSUMÉ

Revue bibliographique: extraction et analyse quantitative des proanthocyanidines et des stilbenes du rasin et du vin

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