Biological properties of brittle star Ophiocnemis marmorata collected from Parangipettai, Southeast coast of India

The classes Ophiuroidea (Brittle stars) and Asteroids (sea stars) belonging to phylum, Echinodermata are characterized by their toxic saponins content. The aim of the present observation was to study the antimicrobial, hemolytic and cytotoxic properties of crude extracts from Ophiocnemis marmorata. The antimicrobial activity of ethanol extract showed maximum zone of inhibition against Staphylococcus aureus (7.0 mm) followed by 5.0 mm inhibition against Escherichia coli and 4 mm against Vibrio parahaemolyticus and  Salmonella typhi. Hemolytic activity was high in goat blood (128 HU) in methanolic extracts. Thin layer chromatography indicates the presence of steroidal compounds in the crude sample. The brine shrimp lethality assay showed maximum mortality at 100% for of 93.6 and 95% ethanol extracts and minimum amount of mortality was noticed at 20% concentration. The regression analysis showed LC50 value of 55.3% in ethanol and 56.3% in methanol extract. Therefore, it is concluded in the present investigation that the steroidal related compounds present in crude extract were responsible for the cytotoxicity activity. Key words: Asteroids, antimicrobial, hemolytic, cytotoxic, steroids.