Production of Extracellular Anti-leukemic Enzyme L-asparaginase from Fusarium solani AUMC 8615 Grown under Solid-State Fermentation conditions: Purification and Characterization of The Free and Immobilized Enzyme

doi:10.21608/ejbo.2016.3776

Production of Extracellular Anti-leukemic Enzyme L-asparaginase from Fusarium solani AUMC 8615 Grown under Solid-State Fermentation conditions: Purification and Characterization of The Free and Immobilized Enzyme

Document Type : Regular issue (Original Article)

10.21608/ejbo.2016.3776

Abstract

POTENTIALITIES of twenty four fungal isolates were investigated for their ability to produce L-asparaginase using modified Czapek’s Dox medium. Fusarium solani AUMC 8615 was selected as the most potent fungal strain for the enzyme production under solid state fermentation (SSF) using agro-industrial residues. Wheat bran supported maximum enzyme production followed by rice bran and corn cob. The optimum conditions for maximum production of L-asparaginase under SSF occurred on the fifth day of incubation at 30°C, pH 8.0, 60% of initial moisture content and supplementation with 0.2% (w/v) glucose and 0.5% (w/v) ammonium sulphate. L-asparaginase was purified to homogeneity by ammonium sulphate precipitation, gel filtration and ion exchange chromatography giving 299.58 purification fold. SDS-PAGE showed that the purified enzyme consists of two subunits of molecular weights 70 and 80 kDa, respectively. The enzyme was efficiently immobilized by covalent binding with activated charcoal giving an immobilization yield of 80.40%. Optimum pH values were 9.0 and 8.0 for free and immobilized enzyme, respectively. While, Optimum reaction temperatures were 37°C and 45°C for free and immobilized enzyme, respectively. After incubation for 2 hr at 37°C, the relative activity of free enzyme decreases to 35% whereas for the immobilized enzyme decreased only to 57% at 45°C.

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