原料碳氮比对丁醇发酵两阶段发酵性能的影响  

Effect of Carbon/Nitrogen Ratio on Butanol Fermentation Performances in Two Periods

作　　者：李鑫[1,2] 李志刚[1,2] 史仲平[1,2] 

机构地区：[1]江南大学生物工程学院,江苏无锡214122 [2]江南大学工业生物技术教育部重点实验室,江苏无锡214122

出　　处：《食品与生物技术学报》2014年第11期1168-1175,共8页Journal of Food Science and Biotechnology

基　　金：国家自然科学基金项目(20976072)

摘　　要：在丙酮丁醇发酵的产酸期和产溶剂期两阶段,向葡萄糖质量浓度固定的培养基中添加不同质量浓度酵母浸粉,比较了不同碳氮比培养下的丙丁梭菌在相应阶段产气、耗糖、产有机酸、发酵相转型和产溶剂等发酵性能的差异.结果表明,在产酸期,适中的碳氮比（46.7-93.4 mol/mol）能够保证菌体以正常速度生长,不至于过分刺激或是抑制有机酸的合成,使发酵顺利完成相转型,有利于缩短发酵周期;在产溶剂期,较高的碳氮比（93.4-186.7 mol/mol）可以有效抑制副产物溶剂丙酮和乙醇的积累,且保持丁醇产量达到12g/以上,从而获得较高的丁醇/总溶剂比例.继而再利用玉米粉、木薯粉和豆饼粉3种含碳氮比差异较大的生物质原料进行丙酮丁醇发酵,验证了上述关于原料碳氮比对丁醇发酵各阶段发酵性能影响效应的结论.Glucose-based media containing different contents of yeast extract were used to cultureClostridium acetobutylicum,either in the acidogenic or in the solventogenic phase.The fermentationperformances in the different period were concerned,including gas production,glucoseconsumption,organic acids and solvents production,and phase-shift,in order to explore the effectsof carbon/nitrogen （C/N） ratio on butanol fermentation performances.The results indicated that amoderate C/N ratio （46.7-93.4 mol/mol） in the acidogenesis could maintain the normal growth rateof strain without large accumulation of organic acids,which resulted in a smooth switch of phase-shift and shortening fermentation time.While a higher C/N ratio （93.4-186.7 mol/mol） in thesolventogenesis was benefit for restraining the synthesis of by-product solvents acetone and ethanol,and simultaneously kept the butanol production upon 12 g/L,leading to a relatively high ratio of butanol to total solvent.Moreover,three kinds of biomasses which contained distinct C/N ratios were used as substrate for butanol fermentation.The results further demonstrate the conclusion acquired above about the impacts on fermentation performances brought by C/N ratio alteration of substrate.

关 键 词：原料碳氮比 丁醇发酵产酸期 丁醇发酵产溶剂期 丙酮丁醇梭菌 

分 类 号：TQ923[轻工技术与工程—发酵工程]