[Enhancement factors of penicillic acid production by Penicillium verrucosum var. cyclopium in foodstuffs (author's transl)].

Main parameters of penicillic acid (P.A.) production by P. verrucosum var. cyclopium were investigated: substrate nature, water content (H: 22-70%), temperature (5-30% degrees C), confined air and incubation delay. 6100, 2820, 1832, 39 and 0.8 mg/kg were the maximal yields obtained in corn, barley, straw, colza and soya. Toxinogenesis rate was greatly enhanced in crushed corn. Maximal yields in corn increased exponentially with H; production and disappearance rates of the free toxin were an increasing function of H and temperature; so, low temperatures may lead to a high accumulation of P.A. within several months. In a confined environment, P.A. concentration was limited for H greater than or equal to 40%; but accession of air induced an accelerated P.A. biogenesis. Maximal yield of P.A. (8000 mg/kg) was obtained in corn with 60% water content, within one week at 25 degrees C.