Antioxidant activity of tropical seaweed sargassum muticum fucoidan

Synthetic antioxidants can have toxic and carcinogenic effects, thus an alternative source of natural antioxidants is needed. Fucoidan from seaweed is a source of natural antioxidants. The objective of this research was to determine the antioxidant activity of fucoidan from Sargassum muticum (Yendo) Fensholt from Alor Island, East Nusa Tenggara. Fucoidan extraction was carried out using distilled water at 85°C. The test parameters observed included: yield, total sugar content, sulfate content, functional group analysis and antioxidant activity with Radical Scavenging Activity (RSA) of the 1,1-diphenyl2picrylhydrazyl (DPPH), ferric Reducing Antioxidant Potential (FRAP), and reducing power methods. The results showed that the fucoidan extract from S. muticum had a yield of 3.87±0.13, the total sugar content of 64.34±2.10 and the sulfate content of 17.72±0.92. FTIR analysis showed that fucoidan from S. muticum had functional group similarities compared to commercial fucoidan from Fucus vesiculosus. The DPPH inhibition activity of S. muticum fucoidan at concentrations of 500, 1,000, 2,000, 3,000 and 4,000 ppm was 35.67±0.96, 39.40±0.66, 42.88±1.46, 45.58±3.66, and 53.57±4.59, respectively. The IC50 DPPH value was 3.75 ppm, and the FRAP value at a concentration of 1,000 ppm was 126.58±5.39 µM g-1. The antioxidant activity of S. muticum fucoidan was lower than that of vitamin C, but not significantly different from that of commercial fucoidan. © 2020, BIOFLUX SRL. All rights reserved.