1,3-丙二醇发酵液的絮凝处理及絮凝细胞的再利用

Flocculation of 1,3-PD Fermentation Broth and Reuse of Cell in Flocs

考察了12种絮凝剂或沉淀剂对1,3-丙二醇发酵液预处理的效果,并探索了壳聚糖絮凝Klebsiellapneumoniae细胞再利用的可行性。以菌体和蛋白质去除率为指标,从12种絮凝剂中筛选出壳聚糖为有效的絮凝剂,并确定了适宜的工艺条件为:温度37℃,搅拌转数300 r/min,pH 5.0,壳聚糖分子质量4万u,浓度0.5 g/L,搅拌20 min,静置15 min。发酵液的菌体和蛋白质去除率分别为99.97%和91.56%。絮凝细胞的发酵实验表明,絮凝的K.pneumoniae可再次利用,菌体浓度高达11.4(OD值)。

The pretreatment of 1,3-PD fermentation broth with flocculants and the reuse of K. pneumoniae in floes were investigated in this paper. Chitosan was proved to be the best among the twelve flocculants, whose performance was evaluated by the cell and protein removal rate. The flocculation performed the best when the temperature was controlled at 37℃, pH was 5.0, the concentration of chitosan was 0.5 g/L with 40k molecular weight, stirring rate was 300r/min, the time of turbidity and settlement were 20 rain and 15min, respectively. Then, it was confirmed that K. pneurnoniae in floe could grow well in fermentation medium.