Fermentation Condition And Properties Of Bacillus Subtilis C-36 Cellulase

A cellulase producing strain C-36 was isolated by our laboratory. The factors including the carbon source, the nitrogen source, the quantity of inoculation, the original pH, the cultural temperature and the cultural time were studied for producing cellulase by Bacillus Subtilis C-36. The results showed that: the optimum carbon source and the nitrogen source were 2%CMC-Na, 2. 5%peptone and yeast extract; the optimum quantity of inoculation was 4%; the optimum original pH was 5. 0; the optimum cultural temperature was 37℃ and the optimum cultural time was 36h. Using the carbon source, the nitrogen source, the quantity of inoculation, the original pH and the cultural time to design L₁₆ (4⁵) orthogonal experiment and finded the optimal fermentation condition of Bacillus Subtilis C-36, the results showed that: the original pH was pH5. 0; the carbon source was 2%; the nitrogen source was 3.5%; the quantity of inoculation was 2%; the cultural time was 36h. Under these conditions, cultured in 37℃,the CMCase activity was 223. 23U/ml which was three point five times of the previous.Followed the optimal fermentation conditions of Bacillus Subtilis strain C-36 producing cellulase to receive crude cellulase. The crude cellulase was isolated and purified by means of ammonium sulfate precipitation , followed by chromatography on Sephadex G-75 and Sephadex G-100. The specific activity of the cellulase increased to 10.42-fold of the source enzyme with an activity recovery of 21. 26%. SDS-PAGE showed its molecular weight was 35 kD.Studied the properties of Bacillus Subtilis strain C-36, the results showed that:the optimum temperature was 65℃. The optimum pH was pH6.8; among pH3. 5 - pH9. 5 , the CMCase was stabile. The cellulase could be...