Evaluation of antioxidant and antibacterial activity of brown seaweed Iyengaria stellata collected from Persian Gulf

Due to the ability of algae in production of secondary metabolites, they can be a potential source of natural compounds used for drug development and treatment of many diseases. Therefore, present study has been performed to determine the antioxidant and antibacterial activity of aqueous extract of brown algae Iyengaria stellata from the coast of Qeshm, Iran. The evaluation of antioxidant activity of algae extract, investigated by measuring the inhibitory effect of hydroxyl radicals, chelating ability of ferrous ions and total antioxidant activity. Antibacterial activity of extract against four strains of pathogenic bacteria, including Escherichia coli, Salmonella typhimurium, Bacillus cereus and Staphylococcus aureus, was evaluated by disc diffusion method and the results were compared with standard antibiotics. The total antioxidant activity, hydroxyl radical scavenging ability and the ability of ferrous ions chelating were high in algae. But the results of antimicrobial tests showed that the aqueous extract of Iyengaria stellata had no antibacterial effect on studied bacteria. According to the results, brown algae Iyengaria stellata can be used as a potential source of antioxidant compounds in food and pharmaceutical industries.