Antioxidant Activity and Cytotoxicity of Organic Extracts from ‎Three Species of Green Macroalgae of Ulvaceae from Persian Gulf

Marine macroalgae are diverse organisms with adaptation for live in stressful environments. The aim of this study was to investigate the biological activities of organic extract; n-Hexane (nH), ethylacetate (E) and methanol (M) of three green alga from family Ulvaceae, Ulva clathrata, Ulva linza and Ulva intestinalis, collected from the coast of Bandar Abbas. In this experimental study, for identification the superior species, the tested activities included antioxidant assay at gradient concentrations by ferric reducing power assay, total antioxidant capacity, total phenolic content, and brine shrimp cytotoxicity activity of these extracts on model organism, Artemia salina. Data analysis was performed by one-way analysis of variance and Duncan's multiple tests at 5% probability level using SPSS 21 software and drawing charts using Excel 2013 software. The more effective algal extracts by maximum antioxidant capacity, were recorded for M extracts of U.intestinalis, E and M extracts of U.linza and U.clathrata. The algal extract exhibited a higher antioxidant activity in comparing to ascorbic acid (as a standard) with significant differences between the extract in different concentrations (p≤0.05). The result showed the highest content of total phenol were recorded for the M extracts of U.linza and U.clathrata which confirmed the findings of other researchers that the increase in free radical scavenging activity of natural extracts is associated with the content of phenolic compounds. The highest brine shrimp cytotoxicity activity was recorded for the nH extracts of U. linza (LC50= 300.78 mg/ml). According to the results, in general, U.linza can be introduced as a priority species for biological properties and in further studies. Three green alga from family Ulvaceae, Ulva clathrata, Ulva linza and Ulva intestinalis, have antioxidant and cytotoxic activity. U.linza due to the high amount of phenol and high antioxidant power can be introduced as a priority species for biological properties.