Optimization of L-asparaginase from Enterobacter aesburiae via response surface approach

Abstract

L-asparaginase, an important biopharmaceutical, has been a boon to cancer patients, especially for the therapeutic treatment of acute lymphoblastic leukemia. However, asparaginase formulations from E. coli and Erwinia species currently being used are associated with potential side effects causing hindrances towards a successful therapeutic treatment. Therefore, optimization and production of asparaginase from varied microbial sources has been the aim of several studies to overcome the hypersensitive and toxicological responses associated with presently used drug formulations. In this study, the possibility of using Enterobacter aesburiae strain R16C1/MT93543isolated from black gram rhizospheric soil sample as L-asparaginase source of industrial importance, was investigated. Different fermentation process parameters for the production of enzyme were optimized using submerged fermentation in shake flask. Box Behnken design was used to optimize and study individual as well as interactive effect of rpm, inoculum size (%) and temperature for asparaginase activity. Comparable values for enzyme activity were obtained from experimental results and software predicted values. As per interaction data obtained for the selected fermentation parameters, rpm, size of inoculum and temperature showed significant effects at interactive levels, thus, showing effect on production of enzyme. A significant improvement in enzyme activity was obtained using optimized environment. Higher enzyme activity of 40.36 U/ml was observed in M9 medium which was 4.4-fold higher than the initial activity of enzyme.