Isolation and Characterization and Some Properties of Cellulase from Fusarium Graminearum Isolated from Corn Cob

Abstract

Breaking down lignocellulosic materials requires the use of cellulases which are recently been exploited for bioremediation. This study is aimed at isolating and characterizing cellulase from Fusarium graminearum isolated from corn cob for possible higher specific activities and greater efficiency for cellulose metabolism. Cellulase from Fusarium graminearum isolated from corn cob was partially purified using dialysis against 50 % glycerol and gel filtration on Sephacryl S- 200 while characterization was carried out using standard methods. The purification process resulted in an overall yield of 10.9 % with a purification fold of 14.4. The partially purified enzyme obtained was of 6477.5 U/mg specific activity and native molecular weight of 35.8 kDa. Our study of the kinetic properties of the enzyme showed a cellulase with high affinity for cellulose with Km and Vmax as 0.1352 mg/ml and 17.86 Units/ml/min. The enzyme displayed its highest performance at 70 oC and pH 4. Mn2+ had little to no impact on Fusarium graminearum cellulase’s activity whereas Mg2+ and Ca2+ somewhat decreased the activity at 5 mM, this was restored to almost 100% at 10 mM. However, Hg2+ and Ba+ had much impact on the activity of the enzyme. This work shows that corn cob Fusarium graminearum cellulase could be exploited as a potential industrial enzyme for targeted waste degradation process because of its high activity and thermostability.