Antibacterial metabolites from the Sri Lankan demosponge-derived fungus, Aspergillus flavipes

Abstract

Sri Lankan sponge-derived fungi are an unexploited resource awaiting exploration for drug leads. Three fungi from the internal tissues of a demosponge collected on the west coast of Sri Lanka were isolated and antimicrobial activities of their crude extracts were evaluated. Aspochalasin B, D, M, asperphenamate and 4-OMe asperphenamate were isolated from the crude ethyl acetate extract of the fungus Aspergillus flavipes. Aspochalasin B and D showed antibacterial activities against Bacillus subtilis (MIC, 16 and 32 μg ml-1 respectively), Staphylococcus aureus and MRSA (MIC, 32 μg ml-1). The results highlight the potential of isolating bioactive secondary metabolites from Sri Lankan sponge-derived fungi.