Proanthocyanidin profile and antioxidant capacity of Brazilian Vitis vinifera red wines

Abstract

The free flavan-3-ol and proanthocyanidin (PA) profile and the antioxidant capacity of wines Vitis vinifera L., 2006 and 2007 vintages, from the São Joaquim region, at southern Brazil, are reported here for the first time. Catechin and epicatechin were the two main monomers in the wine samples, followed by gallocatechin and epigallocatechin; and the PA B1 was the main dimer. The terminal units of the PAs were constituted mainly by catechin units, with the co-presence of epicatechin, gallocatechin, epigallocatechin and traces of epicatechin gallate. The epicatechin and epigallocatechin units were the main constituents of the extension units of PAs with the co-presence of catechin and epicatechin gallate. The values for the mean degree of polymerisation ranged from 4.9 to 9.8. The wine samples demonstrated effective scavenging activity against DPPH and ABTS radicals and against lipid peroxidation in vitro. A positive correlation existed between flavan-3-ol content and antioxidant capacity in vitro.