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Some properties of cellulolytic enzymes produced by Pleurotus sajor-caju JAFM 1017 during its growth in synthetic medium were investigated. The optimum pH of avicelase, CMCase, and β-glucosidase was pH 5.5, pH 4.5 and pH 6.0, respectively. Avicelase and CMCase were stable within pH 5.0 to 6.0 and 4.0 to 6.0, respectively, and β-glucosidase was within pH 5.5 to 6.5. The optimum temperature of avicelase, CMCase and β-glucosidase was the same of 40℃. The enzymes were stable below the optimum temperature, but the enzymes were unstable over the temperature of 50℃, and avicelase was losing about 91.7% of activity at 70℃ for 10 min. The enzyme activity of avicelase and CMCase was increased in proportion to the substrate concentration within 1% and 0.7%, respectively, and β-glucosidase was within 0.1%. The Michaelis constants (Km) of avicelase and CMCase were 30.77㎎ avicel/㎖ and 14.64m Na-CMC/㎖, respectively and β-glucosidase was 5.13㎎ salicin/㎖. The reducing sugar production of avicelase was proportionaly increased until 120 min. and CMCase and β-glucosidase were until 60min. The activity of three cellulolytic enzymes were increased by Ca^(2+) at the concentration of 10^(-2)M, but were inhibited by Hg^(2+), Ag^+.
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