Effect of carbon, nitrogen sources and inducers on protease production by penicillium citrinum lcj222

Protease production by Penicillium citrinum LCJ222 was studied using the six different basal media. Among them, Medium 6 proved to be the best for protease production. Nutritional factors such as carbon, nitrogen, chemical and natural inducer sources were optimized using the selected medium. The protease production was high when lactose was used as a carbon source and yeast extract as the nitrogen source. Among the inducers, natural inducers enhanced maximum protease production when compared to the chemical inducers. Maximum protease activity was observed with black gram husk followed by red gram husk as natural inducers. In the case of chemical inducers, casein served as the best inducer while other chemical inducers inhibited the growth and protease activity. The culture medium with a pH of 9 maximized the production of protease.