Bioactivity- guided fractionation of methylene chloride, ethyl acetate fractions of the sponge Pseudoceratina (Aiolocroia) crassa has led to the isolation and characterisation of (+)-aeroplysinin-1 as the bioactive principle. The structure of the compound was determined by spectroscopic methods.  (+)-Aeroplysinin-1 showed broad spectrum activity against a number of aerobic bacteria, Gram-positive and Gram-negative anaerobes, L1210, P 388 cells, weakly cytotoxic against KB cells in addition to the reported antibacterial activity.

Keywords: Bioactivity-guided isolation; (+) Aeroplysinin-1, Antibacterial; Cytotoxic