USE OF COLLAGEN HYDROLYSATE AS A COMPLEX NITROGEN-SOURCE FOR THE SYNTHESIS OF PENICILLIN BY PENICILLIUM-CHRYSOGENUM

Optimal conditions for both biomass formation and penicillin synthesis by a strain of Penicillium chrysogenum were determined when using a c ollagen-derived nitrogen source. Preliminary investigations were carri ed out in shaken flask cultures employing a planned experimental progr am termed the Graeco-Latin square technique (Auden et al., 1967). It w as initially determined that up to 30% of a conventional complex nitro gen source such as cottonseed meal could be replaced by the collagen-d erived nitrogen source without decreasing the productivity with respec t to the penicillin yield. In the pilot scale experiments using a 30 l stirred tank type of bioreactor, higher penicillin yields were obtain ed when 70% of the conventional complex nitrogen source in the form of cottonseed meal was replaced by the collagen hydrolysate. Furthermore , the maximum rate of penicillin synthesis continued for over a longer period when using collagen hydrolysate as a complex nitrogen source. Penicillin synthesis rates were determined using a linear regression.