Screening of mixed microbial strains degrading cellulose efficiently and study on the conditions of enzyme production

Four mixing modes of 8 microbial strains were determined according to the growth and enzyem production of the strains. By comparing the cellulase activity of the four groups of mixed strains,the group 2 was determined to be the best combination for cellulose degradation. The fermenta-tion conditions were confirmed as: innoculum 8%,100 mL medium contained in 250 ml Erlenmeyer flask,the addition ratio of corncob meal and wheat bran 4:1,yeast extract as nitrogen source,the ratio of carbon and nitrogen source 4:1,initial pH 5.0,fermentation temperature 30℃,shake speed 150 r/min,fermentation time 7 d. With the conditions,the FPA activity reached 281.6U/ml,which was 2.67 and 2.74 times higher than that of the initial Aspergillus miger and Trichoderma.