Journal of Pure and Applied MicrobiologyVol. 9 No. 4

Production of Bacillus subtilis DALX2 Asparaginase: Optimization and Immobilization

Dina I. Abdel Meguid*, Wafaa Mohammed Mahmoud Elwan and Samy A. El-Assar

Department of Botany and Microbiology, Faculty of Science, Alexandria University, Muharam Bek, Alexandria, Egypt.

Received on 13 October 2015 and accepted on 15 December 2015

 

ABSTRACT

Information of asparaginase has been increasingly forthcoming in recent years because of their applications as therapeutic agents in the treatment of certain types of human cancer. In this study, we report, the production of asparaginase from Bacillus subtilis DALX2 using submerged fermentation. An enzyme activity of 130.9 U/ml was reached after 24 h of incubation, at an initial pH of 7.0 and an incubation temperature of 37 C. Plackett-Burman design was employed for optimizing culture conditions. Highest asparaginase was obtained in the medium containing ammonium sulphate as a sole nitrogen source and glucose as the best carbon source. After Plackett-Burman design, an enzymatic titer of 166.1 U/ml was recorded. Moreover, cells were entrapped in Ca-alginate and adsorbed on sponge porous material to increase physical and chemical stability, to avoid leakage of cells or contamination in fermentation medium. Also, evaluation of the efficiency of repeated batch fermentation showed that even after 4 cycles, beads were not disintegrated till the 4th run.

Keywords : Asparaginase, optimization, Plackett -Burman, immobilization, Bacillus subtilis.