Abstract
A suitable chemically defined culture medium was selected and some optimal conditions for the production of the highly immunosuppressive compound, cyclosporin A (Cyc A) are reported. Medium of the following composition was favorable for the production of Cyc A by Fusarium roseum: glucose, 30; NaNO3, 2; KH2PO4, 1; MgSO4.7H2O, 0.5 and KCL, 0.5 (g/l). Maximum productivity of Cyc A was achieved at pH 6.0 when 50 ml of the fermentation medium/250 ml flask, inoculated with five fungal agar discs (6 mm, diameter) of 7-days old F. roseum culture after incubation at 30 ºC at 120 rpm for 7 days.