Two new inhibitors of phospholipase A2 produced by Penicillium chermesinum. Taxonomy, fermentation, isolation, structure determination and biological properties.

Plastatin and the known fungal metabolite, luteosporin, have been isolated from fermentations of Penicillium chermesinum as inhibitors of porcine pancreatic phospholipase A2 (PLA2). Structure 1 for plastatin was deduced from its spectroscopic properties. Plastatin and luteosporin inhibited pancreatic PLA2 competitively with Ki values of 0.89 microM and 12.8 microM, respectively. PLA2 preparations from Naja naja and Crotalus adamanteus were not significantly inhibited by plastatin and luteosporin.