[The Penicillium commune Thom and Penicillium clavigerum Demelius fungi--fumigaclavines A and B producers].

The type strains Penicillium clavigerum VKM F-447 and P. commune VKM F-3233 are found to produce fumigaclavines A and B. Of the seven other strains of these species, only two strains, P. commune VKM F-3088 and F-3491, possess the ability to synthesize these alkaloids. It is suggested that the five other strains under study either lost such an ability or require very specific conditions for the synthesis of these alkaloids.