Some cultural conditions that control production of verrucarin J, a cytotoxic metabolite of Stachybotrys chartarum.

A suitable chemically defined culture medium was selected and some optimal conditions for the biosynthesis of the highly cytostatic and antifungal compound verrucarin J were reported. Medium of the following composition was favourable for the production of verrucarin J by Stachybotrys chartarum: sucrose, 50; NaNO3, 2.0; KH2PO4, 1.0; MgSO4, 0.5; KCl, 0.5; leucine, 1.0 and FeSO4, 0.01 (g/l of distilled water). Biosynthesis of verrucarin J was maximal (11.8 mg/l) at pH 6.5-7.0 and after incubation for 14 days at 25 degrees C.