Studies on the Liquid Fermentation for Nattokinase by Bacillus Natto

This paper investigated the liquid fermentation for Nattokinase by Bacillus natto strain B 2023. The effects of nitrogen source, carbon source, ion composition, interfacial active agent, fermentation temperature and original media pH on production of Nattokinase were investigated. Based on optimized conditions for fermentation, the yield of Nattokinase was 786 IU Urokinase/ml supernatant determined by activity assay on the fibrin plate.