高丁醇比丙酮丁醇梭菌的选育与应用

Breeding of High-Ratio Butano] Strains of Clostridicum acetobutylicum and Application to Industrial Production

设计了专一性分离方法,从土样中分离了多株能产生溶剂的梭菌,经多次单细胞分离、纯化,再经亚硝基胍和甲基磺酸乙酯诱变和抗性筛选,获得几株高丁醇的丙酮丁醇梭菌。对高产菌株的性状稳定性、发酵过程、混合原料应用、温度的影响进行了研究。结果证明菌株性状稳定,丁醇产量为总溶剂的70％;过程为典型的丙酮丁醇发酵,对温度可耐受到39—40℃;能利用玉米和薯干,玉米和高粱进行正常发酵。菌株已在百吨生产罐,连续应用一年以上,丁醇占总溶剂的71.9％,进一步验证了高丁醇性状的稳定性。

Solvent producing strains of Clostridium acetobutylicum were isolated by a specific anaerobic system and purified by repeated single colony plating techniques. The primary isolates were then mutated with NTG and EMS, and selected to obtain high-ratio butanol strains. The culture stability, fermentation courses, effect of temperature, and mixed substrates were studied. The butanol yield amounted to 70% of the total solvent which reached 18g/L in a 7% corn mash. Fermentation analysis demonstrated that all cultures (represented by 2018) was a typlcal Clostridium acetobutylicum fermentation. Besides corn, cheeper raw materials such as sweet potato chips and sorghum could replace part of the corn with an equal high yield of butanol. Industrial application of the culture in 100 ton fermenters for a period of 8 months demonstrated the stability of the culture and the butanol amounted to 67.7-75.0% with an average of 71.9% .