In vitro antioxidant and antimicrobial activities of two Hawaiian marine Limu: Ulva fasciata (Chlorophyta) and Gracilaria salicornia (Rhodophyta).

The antioxidant and antimicrobial properties of two Hawaiian marine algae (Ulva fasciata and Gracilaria salicornia) were evaluated. Ethanolic extracts of these two algae exhibited intracellular reactive 1,1-diphenyl-2-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzthiazoline)-6-sulfonic radical, nitric oxide, superoxide radical, and hydroxyl radical scavenging activities. In addition to the antioxidant activity these algae possessed appreciable antimicrobial activity and total phenolic contents. The overall results have established that these two marine algae could be used to derive bioactive compounds for a possible role as nutraceutical agents.