Effect of m-cresol on the growth of coriolus versicolor and its laccase product ion
间甲酚对杂色云芝(Coriolus versicolor)生长及产漆酶能力的影响

A systematic research of m-cresol biodegradation dynamics by Corio lus versicolor was made. The fermentation characters by C. versicolor in 30 L fermen tor was performed and DC(dried cell), starch, m-cresol consumption, and lac case activity was determined with an 12h interval in three cases of 0mg·L-1, 166.7m g·L-1 and 275mg·L-1 m-cresol. In the absence of the m-cresol, the maximum densi ty of DC was 2600mg·L-1 at 188h, the enzyme activity appeared at 120h, reached the maximum of 82.15U/mL at 228h and then gradually remained stably during the l ater contabescence periods. In the presence of 166.7mg·L-1m-cres ol,, the maxim um DC was 995mg·L-1 at 204h, which was much lower (reduced to 61.73% of nom-cresol) than that in the absence of m-cresol, but the enzyme activity appeare d at 180h, the maximum was 118.36U·mL-1 at 204h, 44.1%higher than tha t in the abse nce of m-cresol, and then was stable without obvious variation in the late r sta ge. In the presence of 275mg·L-1 m-cresol, the maximum DC was 32 0mg·L-1 at 37 2h, which was 12.31% of the absence of m-cresol and 32.16% of the prese nce of 1 66.7mg·L-1 m-cresol. The enzyme activity appeared at 264h, and the maximum one w as112.8U·mL-1 at 396h, which was similar to that at the 166.7mg· L-1 m-cresol co ncentration, indicating that m-cresol could reduce the higher productivity of C. versicolor for laccase. The time-order model of Coriolus versicolor grow th at t hree concentrations of m-cresol above was studied and the kinetics equation s of the growth model were simulated with one order Logistic Equation. Thus, the addi tion of m-cresol doesn't change the growth kinetics model of Coriolus ver sicolor . The kinetics of the starch consumption could be described by a Logistic model, respectively in the above three cases, which indicated that m-cresol coul d, in part, replace or inhibit the consumption of the starch. The degradation kinetic s of m-cresol by C. versicolor in the fermentative liquid was also disc ussed. At m-cresol concentration of 275mg·L-1, its degradation appeared wit h an unstabl e and slow degradation inclination. The different equations also showed that the degradation kinetics of m-cresol by C. versicolor was different at var ious concentrations.