芽孢杆菌发酵生产碱性果胶酶的温度控制策略

Temperature Controlling Strategy for Alkaline Poly-galacturonate Lyase Production with Bacillus sp.

为提高芽孢杆菌WSHB04-02发酵生产碱性果胶酶的产量和生产强度,研究了不同温度（32～41℃）对碱性果胶酶分批发酵动力学参数的影响.结果表明,较高的温度（41℃）能提高细胞对碳源的利用能力并促进细胞快速进入对数生长期;而较低的温度（35℃）则有利于提高菌体在发酵中后期产酶的能力和速率.基于不同温度下的动力学参数,提出了分阶段温度控制策略：发酵时间0～4 h时发酵温度为41℃,4 h之后发酵温度为35℃.经实验验证,采用温度控制策略可使碱性果胶酶的酶活达到53.0 U/mL,生产强度为3315 U/（h·L）,比单一温度模式下的最大值分别提高了23.5%和39.1%.

To enhance the yield and the productivity of alkaline poly-galacturonate lyase by Bacillus sp., the kinetic parameters of batch fermentation at different temperatures ranging from 32 to 41 ℃ were investigated. It was found that the consumption capacity of carbon source increased and the lag stage of cell growth could be shortened with controlling at a higher temperature （41 ℃）. On the other hand, at the lower temperature such as 35 ℃, the production capability and rate of alkaline poly-galacturonate lyase were promoted. Based on the kinetic parameter analysis, a two-stage temperature controlling strategy, in which temperature was controlled at 41℃ in the first 4 h and then shifted to 35 ℃, was suggested and experimentally verified. Following this strategy, the following results were obtained by comparison with that of constant temperature 35 ℃, the maximum alkaline poly-galacturonate lyase activity was 53.0 U/mL, increased by 23.5%, the time of the maximum alkaline poly-galacturonate lyase activity observed was shortened to 16 h, and the productivity was 3315 U/（h.L）, enhanced by 39.1%.