Antibacterial,cytotoxic and larvicidal potential of Dictyota bartayresiana Lamour

Objective:To reveal the antibacterial,cytotoxic and larvicidal activity of Dictyota bartayresiana Lamour(D.bartayresiana).Methods:Phytochemical analysis of various extracts of D.bartayresiana was performed.The antibacterial activity of D.bartayresiana was evaluated by agar diffusion method.The larvicidal activity of crude extract was evaluated as per the protocol described by World Health Organization.The evaluation of LC_(50) value was carried out after 24 h by probit analysis.Cytotoxicity test was carried out using the standard procedure.The LC_(50) and LC_(90) values were obtained from the best-fit line plotted concentration verses percentage lethality.Results:Phytochemical analysis of various extracts of D.bartayresiana showed the presence of steroids,alkaloids,phenolic groups,cardiac glycosides,flavonoids,saponins,tannins and amino acids.It was observed that the methanolic extracts of D.bartayresiana expressed maximum zone of inhibition against Escherichia coli[(9.4±0.2)mm].Crude methanolic extracts of D.bartayresiana showed the highest larval mortality(LC_(50)=166.33 mg/L and LC_(90)=265.69 mg/L)against Culex quinquefasciatus.Similarly,methanolic extracts of D.bartayresiana displayed the highest cytotoxicity with LC_(50) and LC_(90) values at 202.63 and 354.24 mg/L respectively against Artemia salina.Conclusions:The present results revealed the biopotentials of D.bartayresiana and further investigations are needed to elucidate the active principle.