Study On The Cellulase Production By Aspergillus Sydowi LC-562

A new cellulase-producing strain was selected by our research team, which had high CMCase activity proved by the method of Congo red dying. According to its morphological characteristics, this strain was named as Aspergillus sydowi LC-562 temporarily.The study on the enzymatic characteristic of CMCase from A. sydowi LC-562 was carried out. The results showed that it was stable within the pH value range from 4 to 7 and the optimal pH value for reaction was 4.8; It was also stable at 35 ~55 and the optimal reaction temperature was 55 ; The optimal reaction time was 10min.The study of fermentation condition in 250 mL flask was carried out. The results indicated that the carbon sources, nitrogen sources, mineral salt, inoculum and the initial pH value of medium had significant influence on cellulase production and the ratio of component of cellulase group. The highest activity of cellulase (0.256 IU/mL FPase activity, 1.647IU/mL CMCase activity, 0.590 IU/mL CBHase activity, 0.653 IU/mL BGase activity)in broth was detected after 95 hours under the following culture conditions: 1% bran, 3% bean powder, 0.05% MgSO4, 0.2% H2PO4, 1.2 107 /mL inoculum, with initial pH value in medium at 4.8, 28 , 180rpm.The gene clone of CMCase from A. sydowi LC-562 was carried out in brief by PCR method. The results demonstrated that the alkaline method and CTAB method were good method for extracting pRS403 DNA and A. sydowi LC-562 chromosome DNA. But the design of optimum primer for better result of gene clone was required in the future.