Effect of microelements on the biosynthesis of secondary metabolites by the fungus Penicillium citrinum thom VKM F-1079

Penicillium citrinum VKM F-1079 was found to produce clavine ergot alkaloid s and citrinin, a secondary O-heterocyclic metabolite. Citrinin was produce d in the idiophase, whereas the production of ergot alkaloids paralleled fu ngal growth. The addition of manganese ions to the growth medium stimulated the biosynthesis of both citrinin and ergot alkaloids. Zinc ions stimulate d only citrinin synthesis. The presence of these microelements in the growt h medium influenced the proportion between the ergot alkaloids synthesized. Copper, manganese, and iron ions slightly affected fungal growth and alkal oid production. The effect of microelements on the main kinetic parameters of growth and alkaloid production was studied.