Antioxidant activities and phenolic contents of three red seaweeds (Division: Rhodophyta) harvested from the Gulf of Mannar of Peninsular India

The antioxidant activities of methanol extract and its solvent fractions (n-hexane, dichloromethane and ethyl acetate) of three red seaweeds (Hypnea musciformis , H. valentiae, and Jania rubens) collected from the Gulf of Mannar of South eastern coast of India were evaluated, using different in vitro systems, viz., DPPH, ABTS, HO radical scavenging activities, H2O2 scavenging ability, Fe2+ ion chelating ability and reducing potential. Folin–Ciocalteu method was used to determine the total phenolic content of the extracts/fractions, and the results were expressed as mg of gallic acid equivalent (GAE)/g of the seaweed extracts/ fractions. Thiobarbituric acid-reactive substances (TBARS) inhibition assay was employed to assess the ability of the seaweed extracts/fractions to inhibit lipid oxidation