• The Korean Journal of Mycology
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• v.14 no.1
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• pp.37-41
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• 1986

The production of cellulolytic enzymes by Pleurotus sajor-caju JAFM 1017 was stimulated by folic acid and thiamine-HCl. Among the inorganic salts, optimum concentrations of $KH_2PO_4$ and $MgSO_4{\cdot}7H_2O$ were 0.2% (w/v) and 0.04% (w/v), respectively, but other inorganic salts were not effective for the production of the enzymes. The optimum culture temperature and pH for the production were $25^{\circ}C$ and 5.5 for avicelase, and $30^{\circ}C$ and 5.0 for CMCase, and $30^{\circ}C$ and 6.5 for ${\beta}-glucosidase$, respectively.

• The Korean Journal of Mycology
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• v.13 no.4
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• pp.213-219
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• 1985

Among the eight strains, Pleurotus sajor-caju JAFM 1017 was selected as most potent producer of cellulolytic enzymes. The avicelase and CMCase activity reached maximum levels after 10 days, and ${\beta}-glucosidase$ activity reached a maximum level after 19 days. Among the various carbon sources, cellulose powder was most effective for the production of avicelase and ${\beta}-glucosidase$, and Na-CMC (sodium carboxymethyl cellulose) was good for the production of CMCase. The optimum concentration of cellulose powder was 1.0% (w/v), and glucose (1.0%) completely depressed the production of enzymes. Nitrates were effective for the production of enzymes, but nitrites did not support growth. The production of cellulolytic enzymes increased as the concentration of urea increased. The appropriate concentration of urea was 0.054% (w/v).

• The Korean Journal of Mycology
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• v.12 no.4
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• pp.133-140
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• 1984

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 ${\beta}-glucosidase$ 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 ,${\beta}-glucosidase$ was within pH 5.5 to 6.5. The optimum temperature of avicelase, CMCase and ${\beta}-glucosidase$ was the same of $40^{\circ}C$. The enzymes were stable below the optimum temperature, but the enzymes were unstable over the temperature of $50^{\circ}C$, and avicelase was losing about 91.7% of activity at $70^{\circ}C$ 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 ${\beta}-glucosidase$ was within 0.1%. The Michaelis constants (Km) of avicelase and CMCase were 30.77mg avicel/ml and 14.64m Na-CMC/ml, respectively and ${\beta}-glucosidase$ was 5. 13mg salicin/ml. The reducing sugar production of avicelase was proportionaly increased until 120 min. and CMCase and ${\beta}-glucosidase$ 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 $Hg^{2+}$, $Ag^+$.