Free radical scavenging and lipid peroxidation activity of the Shahani black grape.

The present study was designed to evaluate antioxidant activity of different parts of Shahani black grape berries. The antioxidant activity of grape berry juice, seed and skin extracts were measured by the inhibition of lipid peroxidation (Ferric Ammonium Thiocyanate) and free radical scavenging activity (2, 2-diphenyl-l-picrylhydrazyl) methods. Vitamin E and Butylated Hydroxy Toluene (BHT) were used as reference values. The free radical scavenging capacity of grape extracts followed this order: seed methanol extract> skin extract> grape juice> seed hexane extract. Meanwhile, inhibitions of lipid peroxidation of seed methanol and hexane extracts were the highest, grape skin extract activity was intermediate and that of grape juice was the lowest. It seems that the antioxidant activity of samples from grape seed and skin extracts to be mainly based on inhibition of lipid peroxidation, whereas the Antioxidant Activity of grape juice is based on free radical scavenging activity. The results indicate that Shahani black grape has potent antioxidant activity specially on lipid peroxidation and has beneficial effects on human health and help to prevent disease which are caused by free radicals.