The Control of Contaminants in Penicillin Fermentations by Antiseptic Chemicals

Abstract

37 chemicals were tested for their ability to prevent the growth of contaminants and still allow penicillin production in contaminated shake-flask penicillin fermentations. It was found that 0.2% Na2B4O7.10H2O in the fermentation medium delayed the growth of contaminants and allowed normal penicillin production by Penicillium chrysogenum NRRL1951-B25. Different strains of P. notatum and P. chrysogenum varied in their tolerance to Na2B4O7.10H2O; penicillin production by P. chrysogenum NRRL1951-B25 often was increased by 0.2% Na2B4O7.10H2O. Strain NRRL-1951-B25 was acclimatized to grow in normally lethal concs. of Na2B4O7.10H2O, but penicillin production remained inhibited. 80-gallon pilot fermentations with strain NRRL-1951-B25 in a medium containing 0.2% Na2B4O7.10H2O yielded more penicillin at 30 hrs. than similar fermentations without Na2B4O7.10H2O; after 45 hrs. the fermentations without Na2B4O7.10H2O yielded more penicillin than those with Na2B4O7.10H2O.