PURIFICATION AND CHARACTERISATION OF XYLANASE FROM THERMOPHILIC FUNGUS Chaetomium thermophile

摘要

Xylan is the major component of hemicellulose in the cell wall of higher plants. The fungus Chaetomium thermophile produces extracellular xylanase when grown in the presence of complex polysaccharides. Xylanase is important enzyme that is used in food, paper and pulp industry. In the present work, xylanase was purified from Chaetomium thermophile by ammonium sulphate precipitation and gel filtration. During gel filtration, two xylanase fragments were eluted having molecular weight of 70792 and 2512 Da, respectively. The purified enzyme was subjected to kinetic studies and K_m, F_(max), optimum pH and temperature were determined. The xylanase activity was maximum with 1% xylan at pH 4.0 and 60°C. The K_m and F_(max), values were 1.8 mg ml~(-1) and 4 IU ml~(-1) respectively.