Comparison of antioxidant activity of proanthocyanidins from seed of sea buckthorn and grape

The antioxidant activities of proanthocyanidins from seed of sea buckthorn(SBSP)and grape(GSP)were studied with four methods:inhibition of lipid peroxidation and scavenging activity against diphenylpicrylhydrazyl radical,superoxide anion radical and hydroxyl radical.SBSP and GSP exhibited strong scavenging effect on DPPH radical,superoxide anion radical and hydroxyl radical.However,SBSP was more effective at quenching superoxide anion radical and hydroxyl radical than GSP,with the EC50 of 23.95 μg/mL for superoxide anion radical and the second rate constant of 1.355×109 L/g·s for hydroxyl radical-scavenging reaction.SBSP suppressed the initiation rate and propagation rate and prolonged the lag phase and duration of peroxyl radical-induced oxidation in a lecithin liposome model to a greater extent compared to GSP.