Red seaweed (Kappaphycus alvarezii DOTY) from Mollucas island water as potential flavonoid resource of natural antioxidant

The purpose of this research was to find out the best extraction solvent from the point of total flavonoid content and antioxidant activity of Kappaphycus alvarezii. The total flavonoid content of various solvent extracts were determined by spectrophotometer, and calculated as mg QE/g while its antioxidant activity was analysed using DPPH method and calculated as % radical scavenging activity. Total flavonoid content and antioxidant activity data were presented as means ± standard deviation from three replicated experiment. The hexane extract of Kappahycus alvarezii showed higher total flavonoid content (15.93%) and water extract showed lowest content (0.187%). The Radical scavenging activity of various solvent extract was increasing with increased solvent extract concentrations and the highest radical scavenging activity could be obtained in 5 ug/ml hexane extract. It can be concluded that hexane extract of Kappaphycus alvarezii could be potential as a rich resource of natural antioxidant.