C群流行性脑膜炎球菌多糖分批发酵动力学模型的建立

Establishment of batch fermentation kinetics model of polysaccharide of N.meningitidis group C

目的建立C群流行性脑膜炎球菌多糖50 L罐分批发酵动力学模型,为实现对C群流行性脑膜炎球菌多糖发酵过程的工艺控制、优化及其放大提供理论依据。方法利用分批发酵的数据,以Logistic方程建立菌体生长动力学模型,以Leudedeking-Piret微分方程建立产物合成动力学模型,以底物消耗的物料平衡方程建立底物消耗的动力学模型,并应用Origin软件进行模型拟合,获得3个模型的参数。结果菌体的最大比生长速率(μmax)为0.731 2 h-1,最大菌体浓度(Xmax)为3.949 5 g/L,与菌体生长速率关联的产物合成常数(a)为0.004 97 g/(L·h),与菌体浓度关联的产物合成浓度(β)为0.015 44 g/(L·h),菌体对底物的得率(Yx)为1.905 2 g/g,产物对底物的得率(Yp)为0.130 1 g/g,菌体的维持因子(m)为1.070 1。结论建立的动力学模型能较好地反映C群流行性脑膜炎球菌多糖分批发酵过程中菌体生长、C群多糖合成和基质消耗的的变化规律。

Objective To establish the kinetics model to describe the polysaccharide batch fermentation by N. meningitidis group C,and provide a theoretical basis for control,optimization and scale-up of process of polysaccharide fermentation of N. meningitidis group C. Methods Cell growth model was established by Logistic equation,while polysaccharide biosynthesis model by Leudedeking-Piret equation and consumptic model of substrate by equation of substrate balance. The parameters of models were calculated by using Origin software with the data from polysaccharide batch fermentation by N. meningitidis group C. Results The maximum specific growth rate（μmax）was 0. 731 2 h-1,while the maximum biomass（Xmax）was 3. 949 5 g / L,the product formation constants associated with cell growth rate（a）was0. 004 97 g /（L · h）,the product formation constants associated with cell concentration（β）was 0. 015 44 g /（L· h）,the yield of biomass on substrate（Yx） was 1. 905 2 g / g,the yield of product on substrate（Yp） was 0. 130 1 g / g,and the cell maintenance factor（m） was 1. 070 1. Conclusion The models reflected the change regulation of biomass growth, group C meningococcal polysaccharide formation and substrate consumption in batch fermentation process effectively.