In Vitro Antioxidant and Free Radical Scavenging Activity and Chemometric Approach to Reveal Their Variability in Green Macroalgae from South Andaman Coast of India

Abstract

Total phenol, flavonoid, carotenoid and antioxidant activity of four green macroalgae (Halimeda tuna, Halimeda macroloba, Enteromorpha sp. and Acetabularia acetabulum) collected from South Andaman coast were analysed in this study. The results revealed that methanol extract of Enteromorpha sp. showed maximum phenolic, flavonoid and carotenoid content of 5.72±0.13 mg GAE/g, 21.15±1.05 mg RE/g and 47.78±0.46 µg/g respectively. All the analysed macroalgae species exhibited antioxidant activities in dose dependent manner among which Enteromorpha sp. demonstrated greater antioxidant potential. A. acetabulum exhibited greater ABTS (2, 2-azinobiz-3-ethylbenthiazoline-6-sulfonic acid) radical scavenging ability (92%) as evident by its low IC50 (6.30 mg/ml) in comparison to other species. Based on factor analysis, up to two principal components were chosen to explain variability in 10 independent phytochemicals. The antioxidant potential reveals their potential for future applications in medicine, dietary supplements as well as the natural source of immunostimulants.