Study on Optimized Condition for Producing Alkaline Cellulase by Bacillus SP.BA-25 Strain

Bacillus sp.BA-25 was separated from tobacco processing,which can produce alkaline cellulase,and the optimized condition of enzyme producing was also studied well.The results indicated that the bran is the best carbon source in enzyme producing and the bean cake powder is the best nitrogen source.The enzyme activity is the highest in carbon nitrogen ratio 2∶1.NaCl and KH2PO4 are very important in cellulase synthesis.Their suitable amounts are 0.5%～1.0%and 1.0%,respectively.Initial pH can affect enzyme activity and its most suitable pH is 10.Under the optimized culture conditions,the experimental results show that the best fermentation conditions are the inoculum age 24 h,the culture temperature 37 ℃,the rotational speed 160 r/min,the fermentation time 48 h.And it is found that supplement of 1%glucose can increase the activity of alkaline cellulase 24 h later,and the maximal alkaline cellulase activity reached 68.4 U/mL under the optimal conditions.