Screening of Mutant Strains with High Neutral Cellulase Activity and Its Enzyme Production Condition

The mutant strain BE40-39 with relatively high neutral cellulase activity was isolated. The mutant′s ability to produce cellulase increased 2.3 times after treating with UV and γ–ray, and the fermentation properties were different. Avicel was the optimal carbon source. The concentrations of avicel and tryptone were also optimized. The maximum medium cellulase activity reached at 30℃ and pH 4.2 after 5 days′culture.