The dialyzed crude enzyme solution 5mL was loaded on to a DEAE-cellulose (column size 1cm x 33 cm ) equilibrated with 10 mM sodium acetate buffer pH6 at the flow rate of 16 ml/h. The bound protein was washed with 100 ml of the same buffer and eluted with linear gradient of NaCl 0-1 M in the same buffer 100 ml+100 ml with 1 M NaCl .