Antibacterial, antifungal and cytotoxic effects of a sea cucumberHolothuria leucospilota, from the north coast of the Persian Gulf

Abstract

Bioactive compounds of gonad, respiration tree, cuvierian organ, and body wall of the sea cucumberHolothuria leucospilotacollected from the north coast of the Persian Gulf were extracted using ethyl acetate, methanol and water–methanol solvents. Extracts were evaluated for their antibacterial and antifungal activities againstAspergillus niger,Candida albicans,Staphylococcus aureus,Pseudomonas aeruginosaandEscherichia coli. The activity was determined using the disc diffusion test. Cytotoxic activities of the extracts were determined by brine shrimp lethality assay. Results demonstrated that theA. nigerwas shown to be the most sensitive microorganism followed byC. albicans. The inhibition zone againstA. nigerandC. albicanshad minimum inhibitory concentrations ranging from 3 to 7 μg/ml. The highest antifungal activity was found in G (water–methanol) with an inhibition zone of 50 mm againstA. nigerat 18 μg/ml extract concentration continuing with CT (methanol) with 46 mm inhibition zone againstA. nigerat 18 μg/ml extract concentration. The highest cytotoxic effect of methanol extract was found with LC50values of about 40.31 μg/ml in the gonad organ fromH. leucospilotacontinuing with the respiration tree organ with LC50values of about 72.49 μg/ml.