木糖发酵拜氏梭菌的分离及发酵特性

Isolation and fermentation characteristics of Clostridium beijerinckii utilizing xylose

【目的】分离获得同步利用葡萄糖与木糖的产丁醇菌株并对其五、六碳糖代谢动力学特性进行研究.【方法】以木糖为唯一碳源培养基,富集、筛选获得利用木糖产丁醇菌株;通过显微形态特征及16SrRNA序列分析对目的菌株进行分类鉴定;采用不同配比(2∶1、1∶2与1∶1)葡萄糖与木糖混合糖培养基对菌株的五、六碳糖代谢动力学特性进行研究.【结果】获得一株产丁醇菌株,鉴定菌株S3为Clostridium beijerinckii,命名为C.beijerinckii SE-2;葡萄糖与木糖代谢速度比较发现其对葡萄糖与木糖的利用速率基本相当,混合糖发酵动力学分析进一步说明菌株对木糖的代谢不受葡萄糖的阻遏,混合糖的利用速率分别为0.56,0.56,0.53g/L/h.【结论】菌株C.beijerinckii SE-2具有很好的葡萄糖与木糖同步代谢及产丁醇能力,具有一定以木质纤维素水解液生产生物丁醇的应用前景.

【Objective】In order to isolate the strain which could utilize pentose and hexose simultaneously and study the characteristics of metabolism dynamics.【Method】Medium with xylose was used as the sole carbon source to isolate butanol producing strain and the isolated strain was identified by using morphological characteristic and 16S rRNA gene sequence methods;and the kinetic characteristics of the pentose and hexose utilization was also studied with different initial glucose to xylose ratios(2∶1,1∶2 and 1∶1).【Result】The result of identification revealed that strain S3 could be classified as Clostridium beijerinckii,and was named C.beijerinckii SE-2.A similar rate of sugar consumption could be observed in two cultures,suggesting that this strain could use either glucose or xylose as the substrate and it possesses a similar capability to degrade these two sugars.In addition,the mix sugars utilization rate was similar(0.56,0.56,0.53 g/(L·h)).【Conclusion】The result indicates that C.beijerinckii SE-2,a highly efficient butanol producing bacteria which could utilize pentose and hexose simultaneously,and might be a potential candidate for the butanol production from hydrolysate.