FOAM BEHAVIOR OF BIOLOGICAL MEDIA .3. PENICILLIUM-CHRYSOGENUM CULTIVATION FOAM

If no antifoaming agent, AA, is present, the foaminess Σ of Penicillium chrysogenum cultivation media depends on the cultivation time. With increasing cultivation time, tF, Σ increases, passes through a maximum and then decreases. In the presence of AA, the foaminess does not depend on tF. In the absence of AA, the foaminess is not influenced by the gas flow rate. In Presence of AA, Σ increases, with increasing gas flow rate, passes through a maximum and then diminishes. The surface tension, σ, diminishes with tF. However, σ is also a function of tM and σ attains its equilibrium surface tension value, σequil, at tM=tDG. The foaminess can be described as a simple function of tDG. The time dependence of σ can be evaluated by the following equation: {Mathematical expression} where V is the dimensionless surface tension b and n are constants The complex Penicillium chrysogenum medium can be treated analogously to the simple protein solutions considered earlier. (Kalischewski et al., 1979). © 1979 Springer-Verlag.