[The influence of medium composition on alkaloid biosynthesis by Penicillium citrinum].

The fungus P. citrinum produces secondary metabolites, clavine ergot alkaloids (EA), and quinoline alkaloids quinocitrinines (QA) in medium with various carbon and nitrogen sources and in the presence of iron, copper, and zinc additives. Mannitol and sucrose are most favorable for EA biosynthesis and mannitol is most favorable for QA. Maximum alkaloid production is observed on urea. Iron and copper additives in the medium containing zinc ions stimulated fungal growth but inhibited alkaloid biosynthesis. The production of these secondary metabolites does not depend on the physiological state of culture, probably due to the constitutive nature of the enzymes involved in biosynthesis of these substances.