Production and Optimization of Extra Cellular L-asparaginase by Fusarium solani Isolated from Withania sominifera

Abstract

L-asparaginase has been commonly used for the treatment of acute lymphoblastic leukemia in children. It is also used in food industry to reduce acrylamide formation during preparation of fried food items containing starch at high temperature. L-asparaginase is widely distributed among the microorganism, animals, and plants. Medicinal plant Withania sominifera was identified as potential novel source for L-asparaginase enzyme because of its high specific activity of the enzyme. So the fungi reside in the plant was studied for the identification of new enzyme source. Different fungal species were isolated and screened initially for the production of extracellular L-asparaginase using Czapek’sDox medium. The enzyme hydrolyzed zone and unhydrolyzed zone of L-asparagine were standardized using different dyes. The strain Fusarium solani showed maximum zone diameter (2.7 cm). Further, it was observed that maximum activity of 3.58 IU was achieved by employing orange peel as substrate. Various physical and nutritional parameters were optimized under solid state fermentation as orange peel as substrate and found that, maximum activity obtained with incubation temperature 35°C at pH 5 with potassium di hydrogen phosphate (0.25%), magnesium ions (0.002%) and sucrose (1%) as the best phosphate, metal ions and carbon source respectively.

Key words:

• L-asparaginase
• Fusarium solani
• Czapek Dox medium