Wu Jing, Zhou Yu-Jie, Zhang Wen, Cheng Ke-Ke, Liu Hong-Juan, Zhang Jian-An
Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084, China.
School of Chemical Engineering and Energy Technology, Dongguan University of Technology, Dongguan, 523808, China.
AMB Express. 2019 Sep 24;9(1):153. doi: 10.1186/s13568-019-0879-1.
Fermentation of chemicals from lignocellulose hydrolysate is an effective way to alleviate environmental and energy problems. However, fermentation inhibitors in hydrolysate and weak inhibitor tolerance of microorganisms limit its development. In this study, atmospheric and room temperature plasma mutation technology was utilized to generate mutant strains of Enterobacter cloacae and screen for mutants with high inhibitor tolerance to acid hydrolysate of corncobs. A highly inhibitor-tolerant strain, Enterobacter cloacae M22, was obtained after fermentation with non-detoxified hydrolysate, and this strain produced 24.32 g/L 2,3-butanediol and 14.93 g/L organic acids. Compared with that of the wild-type strain, inhibitor tolerance was enhanced twofold with M22, resulting in improvement of 2,3-butanediol and organic acid production by 114% and 90%, respectively. This work presents an efficient method to screen for highly inhibitor-tolerant strains and evidence of a novel strain that can produce 2,3-butanediol and organic acids using non-detoxified acid hydrolysate of corncobs.
木质纤维素水解产物中化学物质的发酵是缓解环境和能源问题的有效途径。然而，水解产物中的发酵抑制剂以及微生物对抑制剂的耐受性较弱限制了其发展。在本研究中，利用常压室温等离子体诱变技术构建阴沟肠杆菌突变株，并筛选对玉米芯酸水解产物具有高抑制剂耐受性的突变体。用未脱毒的水解产物发酵后获得了一株高抑制剂耐受性菌株阴沟肠杆菌M22，该菌株产生了24.32 g/L的2,3-丁二醇和14.93 g/L的有机酸。与野生型菌株相比，M22的抑制剂耐受性提高了两倍，2,3-丁二醇和有机酸产量分别提高了114%和90%。这项工作提出了一种筛选高抑制剂耐受性菌株的有效方法，并证明了一种新型菌株能够利用未脱毒的玉米芯酸水解产物生产2,3-丁二醇和有机酸。
