Antioxidative activity of resveratrol and its derivatives isolated from seeds of Paeonia lactiflora.

Seven stilbenes, a new cis-epsilon-viniferin and the six known stilbenes, trans-resveratrol, trans-resveratrol-4'-O-beta-D-glucopyranoside, trans-epsilon-viniferin, gnetin H, and suffruticosol A and B, were isolated and identified from seeds of Paeonia lactiflora. The antioxidative activity of these stilbene derivatives was evaluated against the 2-deoxyribose degradation and rat liver microsomal lipid peroxidation induced by the hydroxyl radical generated via a Fenton-type reaction. Among these stilbenes, trans-epsilon-viniferin and gnetin H significantly inhibited 2-deoxyribose degradation and lipid peroxidation in rat liver microsomes. In addition, cis-epsilon-viniferin, and suffruticosol A and B also exhibited moderate antioxidative activity. These results suggest that resveratrol dimers and trimers, together with resveratrol from seeds of Paeonia lactiflora may be useful as potential sources of natural antioxidants.