粪产碱杆菌在不同底物限制性条件下连续培养

Continuous Cultivation of Alcaligenes faecalis in Medium Containing Different Sole Limited Substrates

为了提高菌体阶段菌体的生长密度、对分批发酵有一些优化指导作用,对菌体本身特性进行了研究。以葡萄糖、氯化铵分别为限制性底物,对粪产碱杆菌进行了连续培养,模拟了粪产碱杆菌在不同的营养条件下的发酵情况,并对连续培养特性和动力学性质进行了分析。结果表明:在葡萄糖限制条件下粪产碱杆菌的比生长速率与限制性底物浓度的关系符合Monod方程,建立了相应的模型方程;同时还建立了两种限制条件下的葡萄糖的消耗动力学模型;并对两种限制条件下的维持系数、菌体产率进行了比较。比较表明:葡萄糖限制对菌体产率的影响比氯化铵限制时大,在氯化铵限制条件下菌体产率最大为0.4 g/(h.L),而葡萄糖限制条件下菌体产率最大只为0.3g/(h.L)左右;氯化铵限制条件下的维持系数是葡萄糖限制条件下的2倍,说明发酵过程中主要的维持消耗是在产胶期热凝胶的合成过程中。

In order to increase the density of cell and give more guides to optimization of batch fermentation, a Study on the characteristics of Alcaligenes faecalis should be carried out. In this paper, with continuous cultivation simulating fermentations in different nutritional conditions, continuous cultivation of Alcaligenes faecalis with glucose and ammonium chloride as a sole limited substrate were carried out respectively, and kinetics and characteristics of continuous cultivation were investigated. The experimental results showed that Monod equation can express the relationship between the specific growth rate and the glucose concentration under limited glucose, and then model equation was built. Besides, under two sole limited substrates, model equations of glucose consumption were built and comparison of the biomass yield, the growth maintenance coefficient were carried out. The comparison showed that the biomass yield under limited glucose, 0.3 g/（h L）, is smaller than that under limited ammonium chloride, 0.4g/（h L）. And the growth maintenance coefficient under limited glucose is two times than that under limited ammonium chloride. So the glucose consumption for maintenance is mainly in the stage for curdlan production.