Coordination characteristics of proanthocyanidins from Picea koraiensis Nakai's cones and the antioxidant activity of the coordination compound

The coordination of second purified proanthocyanidins with Fe2+, Zn2+and bovine serum albumin was studied. The effect of proanthocyanidins concentration, temperature and pH on coordination characteristics was investigated and the coordination conditions were optimized. The antioxidant activity of the coordination compound was evaluated. Results showed that the rate of proanthocyanidins coordinated with Fe2 +, Zn2 +and bovine serum albumin was 89.12%±1.06%, 88.31%±0.87% and 91.78%±1.25% respectively under the optimized conditions. The physiological activity of proanthocyanidins increased after coordinated. The activity of scavenging free radicals and reducing power were enhanced. A dose-response relation between concentrations and antioxidant activity was found, for which a good development prospects was expected.