Production and degradation of alkaline protease in batch cultures of Bacillus subtilis ATCC 14416

The production of alkaline protease from Bacillus subtilis ATCC 14416 was studied. Inorganic nitrogen compounds in the medium were found to show inhibitory effects on the enzyme formation. The pH variations of the culture broth gave indications of the start and the end of the enzyme production period and thus provided a useful indicator for process control. The rapid deactivation of protease after the end of the production period was studied, and ways to stabilize the enzyme were discussed.