Title: Screening of in vitro antioxidant activity of bark extracts of Polyalthia longifolia
Abstract: The purpose of this study was to evaluate the antioxidant activity of the bark extracts of Polyalthia longifolia. Methanol, ethanol and aqueous extracts of bark of P. longifoliawere evaluated 1,1-diphenyl-1,2-picryl hydroxyl (DPPH) radical scavenging, hydrogen peroxide scavenging, hydroxyl radical scavenging, superoxide radical scavenging, total phenolic content, total antioxidant capacity, and peroxy radical scavenging activity. These antioxidant activities were compared using α-tocoperol as the standard. Among the various extracts, methanol extract showed good antioxidant activity and aqueous extract showed very low activity in all the antioxidant assays. This study confirms the antioxidant activity of different extracts of bark of P. longifolia. Key words: DPPH, Polyalthia longifolia, antioxidant.