Antimicrobial activity of marine sponge extracts of offshore zone from Nay Band Bay, Iran

In vitro antimicrobial activity of six sponge species (Porifera), collected from offshore zone of Nay Band Bay, Bushehr, (Iranian coast of Persian Gulf), against certified strains of bacteria (two Gram-positive: Bacillus subtilis ATTC 6633, Staphylococcus aureus ATCC 25923 and two Gram-negative: Pseudomonas aeroginosa ATCC 27853, Escherichia coli ATCC 25922) and fungi (Candida albicans ATCC 10231, Aspergillus spp. PTCC 5266, Penicillium spp. PTCC 5251) were conducted in this study. Three extracts of each sponge with solvents of different polarity were evaluated (methanol, ethyl acetate, and n-hexane) through the disk diffusion assay. The results showed that 83.3% (15 from 18 extracts)of the sponge extracts presented activity against at Least one bacterial strain and 83.3% were active against at least one fungus. On the basis of this study, the activity against bacteria and fungi was moderate. Also, minimum inhibitory concentrations (MICs) of the extracts with desirable activities (inhibition zone more than 9 mm) in the previous stage were assessed. Among the 18 extracts, 83.3% showed activity against some of the four bacteria. The three most active sponges against four tested bacteria were: Gelliodes spp., Spheciospongia spp. 1, Spheciospongia spp.2. Among the 18 extracts, 66.6% showed activity against Candida albicans and the most active sponge against yeast was Spheciospongia inconstans. This is the first report of biological activities of marine sponges from Iranian coast of Persian Gulf. (C) 2008 Elsevier Masson SAS. All rights reserved.