Optimization of culture media for L-asparaginase production by newly isolated bacteria, Bacillus sp. GH5

Abstract

The enzyme L-asparaginase has been extensively studied by many researchers mainly because of its considerable therapeutic properties. Producing a convenient quantity of L-asparaginase can be conducted either by discovering new microbial sources with higher enzyme production or by manipulating the medium components for known microbial sources. The present paper discusses the studies carried out in order to enhance the production of L-asparaginase by newly isolated bacteria, Bacillus sp. GH5. Based on the results obtained from media optimization studies, a modified media was developed for optimal L-asparaginase production. Concisely, screening of the nutrients using a proper statistical design showed that tapioca starch, gelatin, ammonium oxalate, CaCO3, and L-asparagine were respectively the most important sources for carbon, organic nitrogen, inorganic nitrogen, mineral salt, and amino acids. The composition of the optimized medium was the following (per 1 L): 5.0 g L-asparagine; 0.5 g MgSO4 · 7H2O; 6.0 g NaHPO4 · 2H2O; 3.0 g (NH4)2C2O4; 0.5 g CaCO3; 0.014 g CaCl2 · 2H2O; 2.0% w/v tapioca starch; 5.0 g gelatin; and 15.0 g agar.