Comparison of antioxidant activity of alginate extracted by acidic method from two species of brown algae, sargassum vulgare and Padina pavonic

Alginates are polysaccharides found in brown algae having the most content in marine biopolymers. The present study investigates to extract the alginate using acidic method at PH=2 and comparing antioxidants activity of the extracted alginate at different concentrations from the brown macroalgae of S. vulgare and P. pavonica. According to results of the antioxidant measurement of total phenol content, free hydroxyl radical content, free, total antioxidant activity in three concentrations (20, 100, 200 mg/ml), free superoxide radicals in two concentrations (4.26, 41.45 µg/ml), chelating power in three concentrations (0.1, 0.5 and1 mg/ml), S. vulgare algae alginate was higher than P. pavonica algae alginate (P<0.05). Also, percentage of the free radical scavenging of DPPH was observed at a concentration of (150 µg/ml) by S. vulgare alginate and a concentration of (20 µg/ml) by algae alginate P. pavonica) P<0.05). No significant difference was found between the algae alginates in the reduction test in any of the concentration intervals) P>0.05). Due to the high antioxidants capacity of the studied alginates in this study, alginate can be introduced as a potential source of natural antioxidant compounds in the food, medical, cosmetic and health industries.