Optimization of Fermentation Conditions of Cellulase Produced by a Marine Aspergillus Niger with Response Surface Methodology and Variable Temperature Culture
1. Ocean Research Center of Zhoushan, Zhejiang University, Zhoushan 316000, China;
2. College of Biological Engineering, Hubei University of Technology, Wuhan 430000, China;
3. College of Life Science, Zhejiang University, Hangzhou 310058, China;
4. College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
Abstract：The response surface analysis and variable temperature culture were used to optimize the liquid fermentation conditions for the production of salt-tolerant cellulose by a marine Aspergillus niger. Firstly, the single factor tests were carried out to determine the carbon source, nitrogen source, temperature, surfactant, inoculum amount, liquid volume and initial pH. Then the Plackett-Burman (PB) design was used and the wheat bran and Tween-80 were identified as the two major components that affect the filter paper activity (FPA). The concentrations of these two components were ascertained to be close to the maximum enzyme activity area by steepest ascent path. Finally, the response surface analysis was used to obtain the optimal fermentation medium formulation of salt-tolerance cellulose and the variable temperature experiment was carried out to determine the optimum culture temperature. The optimal formulation was determined as 40 mL of medium consisting of 5.53 % wheat bran, 0.5 % corn steep liquor, 0.2 % KH2PO4, 0.197 % Tween-80 in a 150 mL flask, and the optimal fermentation conditions were initial pH of 5, inoculum concentration of 8%, liquid volume of 40 mL at 180 r/min, culture temperature at 37 ℃ for 2 days followed at 28 ℃ for another 2 days. The maximum FPA under the optimized conditions was 0.566 U/mL, which was increased by 94.5 % compared with the 0.283 U/mL obtained before optimization.
Chen Zuoguo 1,4,Zheng Gang 1 et al. Optimization of Fermentation Conditions of Cellulase Produced by a Marine Aspergillus Niger with Response Surface Methodology and Variable Temperature Culture[J]. 化学反应工程与工艺, 2016, 32(5): 473-480.
