title: Red wine phenolic complexes and their in vitro antioxidant activity.
abstract: Phenolic complexes are a major group of polyphenols in aged red wine. The objective of this work was to evaluate the in vitro antioxidant activity of the phenolic complexes. Thus, red wine polyphenols were fractionated into various fractions including monomers, oligomers, polymers, anthocyanins, and complexes. The in vitro antioxidant activities of these fractions and other phenolic standards (catechin, epicatechin, quercetin, and malvidin 3-glucoside) as well as ascorbic acid were verified by DPPH* test. On the other hand, the variation of antioxidant activities during the reaction between epicatechin and malvidin 3-glucoside mediated by acetaldehyde in a model wine solution was also monitored. The results showed that both the phenolic complex fraction and newly formed condensation products between epicatechin and malvidin 3-glucoside maintain antioxidant activities as strong as those of their compositional phenolics. This work provides, for the first time, direct evidence about the in vitro antioxidant activities of red wine phenolic complexes.
authors.affiliation: L-INIA Dois Portos, Instituto Nacional de Recursos Biologicos, I.P., Quinta da Almoinha, 2565-191 Dois Portos, Portugal. evn.sun.baoshan@mail.net4b.pt
authors.forename: Baoshan
authors.initials: B
authors.lastname: Sun
authors.forename: Isabel
authors.initials: I
authors.lastname: Spranger
authors.forename: Jingyu
authors.initials: J
authors.lastname: Yang
authors.forename: Conceiço
authors.initials: C
authors.lastname: Leandro
authors.forename: Lei
authors.initials: L
authors.lastname: Guo
authors.forename: Sónia
authors.initials: S
authors.lastname: Canário
authors.forename: Yuqing
authors.initials: Y
authors.lastname: Zhao
authors.forename: Chunfu
authors.initials: C
authors.lastname: Wu
mesh_terms: D000079:Acetaldehyde / Q000737:chemistry; D000872:Anthocyanins / Q000737:chemistry; D000975:Antioxidants / Q000494:pharmacology*; D002392:Catechin / Q000737:chemistry; D005591:Chemical Fractionation; D005419:Flavonoids / Q000032:analysis / Q000302:isolation & purification; D005960:Glucosides; D010636:Phenols / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D059808:Polyphenols; D014920:Wine / Q000032:analysis*
chemical_list: D000872:Anthocyanins; D000975:Antioxidants; D005419:Flavonoids; D005960:Glucosides; D010636:Phenols; D059808:Polyphenols; C458419:malvidin-3-glucoside; D002392:Catechin; D000079:Acetaldehyde