[Biosynthesis of penicillin and the biphasal development of a P. chrysogenum culture]

The two-phase pattern of penicillin biosynthesis was observed only under definite cultivation conditions. When the conditions of the culture growth changed, the productivity curve also changed. The most high productivity levels on the glucose medium and the medium with glucose and lactose were noted at the beginning and in the middle of the process respectively. Under more or less equal conditions the productivity remained at the same level.