Assessment of antioxidant activity, total phenolic content and in- vitro toxicity of Malaysian red seaweed, Acanthophora spicifera

Various extracts of local marine red algae, Acanthophora spicifera were evaluated for antioxidant activity, total phenolic content and in-vitro toxicity. The antioxidant activity was measured using DPPH (1, 1-diphenyl-2-picrylhidrazyl) method, while Folin-Ciocalteu method was used for the total phenolic content. The cytotoxicity of the extracts were evaluated using invitro brine shrimp lethality assay. Chloroform extract showed the highest antioxidant activity of 50.098 ± 2.104% and EC50 value of 0.789 mg ml . A positive correlation between total phenolic content and antioxidant activity of the extracts was observed for both extractions. Ethyl acetate extract from Soxhlet, exhibited the highest total phenolic content of 40.583 ±1.161 GAE; μg mg dry extract and consequently had strong antioxidant activity (45.596 ±1.198%). The extract showed cytotoxic effect with LC50of 635.47μg ml -1 for acute and 275.72 μg ml for chronic,