Antioxidant properties of some filamentous green algae (Chaetomorpha Genus)

The antioxidant activity and the contents of total phenolics and flavonoids were quantified in the methanolic extracts of four Chaetomorpha species including C. aerea, C. crassa, C. linum and C. brachygona. Eight samples of Chaetomorpha plants were collected from five locations along the northern coasts of the Persian Gulf in south of Iran from December 2010 until October 2011. Methanolic extracts of the seaweeds were assessed for their antioxidant activity using DPPH radical scavenging assay. C. linum showed highest antioxidant potential with a relatively low IC50 (1.484 ± 0.168 mg mL-1), the highest flavonoid content (18.177 ± 2.238 mg RE g-1 ) and a relatively high content of phenolics (2.895 ± 0.415 mg GAE g-1) in comparison with the other species. C. crassa, which was collected from two different areas, showed lowest antioxidant activity and lowest phenolics and flavonoid contents than other species. Results revealed that IC50, total phenolics and flavonoid content were influenced by the time of collection and location. Also there were positive correlations between the phenolic and flavonoid contents with DPPH radical scavenging activity (p