The nutritional and cultural conditions in shake flask culture for improved production of L-Asparaginase from endophytic fungus Fusarium sp. LCJ324: A sequential statistical method

Abstract

L-Asparaginase has a greater demand due to its potential application in the food industry as well as in the pharmaceutical industry. To meet this demand, optimization of nutritional as well as physical conditions is critical for scaling up the production of L-Asparaginase. This study aims to achieve enhanced L-Asparaginase production, a therapeutic enzyme from the endophytic fungus Fusarium sp. LCJ324 isolated from Glycosmis mauritiana (Lam.) Tanaka belonging to the Rutaceae family. Fusarium sp. LCJ324 exhibited L-Asparaginase activity of 8.75 ± 0.55 U mL-1 in modified Czapek Dox broth, the highest among all the seven different media tested by submerged fermentation. Different sources and concentrations of carbon, nitrogen and amino acid inducers (nutritional factors) as well as pH and temperature (physical parameters) were optimized to achieve enhanced L-Asparaginase production. Maximum L-Asparaginase activity of 19.94 ± 0.35 U mL-1 was obtained at 30º C with dextrose (3 g L-1), ammonium sulphate (30 g L-1), and L-Asparagine (20 g L-1) at pH 6. Response Surface Methodology was employed for statistical optimization of minimum and maximum levels of the selected parameters. The levels of parameters suggested by the response surface methodology for maximum production of L-Asparaginase were similar to the conventional optimization. A 2.29 fold increase in L-Asparaginase production was obtained through conventional and statistical optimization.

Keywords

• modified czapek dox broth
• l-asparagine
• one factor at a time
• response surface methodology
• submerged fermentation