Optimization and modeling of production and partial characterization of protease from Bacillus licheniformis NRS 1264

BACKGROUND

With the developments in enzyme technology and their wide range of use, proteases have become one of the important industrial enzyme groups in the market. Therefore, there is a continuing need to explore new protease producers to meet various demands in industry. This study aimed to optimize and model protease production by Bacillus licheniformis NRS 1264, as well as to partially characterize the enzyme.

RESULTS

Characterization studies showed optimum temperature and pH values of the enzyme as 55 °C and 5.5, respectively. It was also found that the presence of 5 mmol L⁻¹ of MnSO₄ increased protease activity by 37%, whereas the same amount of CoCl₂ and EDTA decreased the activity by 20% and 37%, respectively. Additionally, the enzyme retained 95% of its maximum activity even after 30 days of storage at 4 °C. Furthermore, results of optimization studies indicated the optimum glucose, peptone and casein concentrations in the production medium as 1.25, 7.20 and 10.98 g L⁻¹, respectively. Under these conditions, maximum enzyme activity was measured as 5078 U mL⁻¹, which was approximately fourfold higher compared to the lowest enzyme activity value obtained in a one-factor-at-a-time experiment. Finally, modeling studies indicated that the modified Gompertz model represented protease production more successfully compared to the modified logistic model by having less error and R², bias factor and accuracy factor values closer to 1.

CONCLUSION

This is a unique study bringing a broadening of knowledge to the potential industrial level production of this highly potent protease enzyme. © 2025 The Author(s). Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).