A carboxymethylcellulose solution (CMC, 1%) was prepared in 0.2 M sodium acetate buffer (pH 4.2). One milliliter of the CMC solution was incubated with 1 mL of the crude enzymatic extract at 50 C for 10 min (Ogawa et al., 1982) and the amount of reducing sugar was measured by the DNS method (3,5-dinitrosalicylic) according to Miller (1959).