Free radical and reactive oxygen species scavenging activities of peanut skins extract

Peanut skin, a low economic value by-product of the peanut industry, is rich in potentially health promoting compounds. The major objective of this study was to investigate free radical and reactive oxygen species scavenging activities of water soluble extracts from defatted peanut skins (EPS) employing various in vitro assay systems. The total phenolic content of EPS was 0.097 g gallic acid equivalents/g of skin tested, and the total flavonoid content of EPS was 0.065 g catechin equivalents/g of skin tested. EPS at 500 mu g/ml exhibited 97.1% of DPPH radical scavenging activity and 98.6% of inhibition of erythrocyte hemolysis, and showed 98.6%, 89.1% and 85.3% of scavenging activities on O-2(center dot-), H2O2 and OH center dot, respectively, and also effectively exerted 76.6% of Fe2+ chelating activity. These results suggested that EPS might be beneficial as a potent antiradical and antioxidant and effectively employed as an ingredient in food applications. (c) 2006 Elsevier Ltd. All rights reserved.