Optimization of chitosanase production by Bacillus mojavensis EGE-B-5.2i.

Maximum production of industrially important enzymes such as chitosanases through media optimization still holds foremost interest. The present study was conducted to improve chitosanase activity of an indigenous strain identified as Bacillus mojavensis. Initially, carbon and nitrogen sources were optimized by one-variable-at-a-time approach. Further, fermentation medium was optimized using Plackett-Burman (PB) and central composite designs (CCD). PB verified soluble starch (SS), colloidal chitosan (CC) peptone, and NaCl as most significant variables affecting chitosanase production. CCD results predicted the optimum concentrations of SS, CC, peptone, and NaCl as 7.8, 7.0, 6.5, and 2.7 g L-1 , respectively to achieve maximum chitosanase activity (21.1 U ml-1 ). Discovery of the novel optimal medium has improved chitosanase production by B. mojavensis up-to 9.5 folds. Lastly, 18.6 U ml-1 chitosanase activity was achieved in stirred tank bioreactor using optimal medium, which is quite satisfactory to proclaim this strain as a potential candidate to provide commercial chitosanase.