文献类型：期刊文献

英文题名：High tolerance and physiological mechanism of Zymomonas mobilis to phenolic inhibitors in ethanol fermentation of corncob residue

作者：Gu, Hanqi[1];Zhang, Jian[1];Bao, Jie[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2015

卷号：112

期号：9

起止页码：1770

外文期刊名：BIOTECHNOLOGY AND BIOENGINEERING

收录：;EI(收录号：20152000858313);WOS:【SCI-EXPANDED(收录号:WOS:000358640600005)】；

基金：Contract grant sponsor: National Basic Research Program of China Contract grant number: 2011CB707406/2013CB733902 Contract grant sponsor: National High-Tech Program of China Contract grant number: 2012AA022301/2014AA021901 Contract grant sponsor: Natural Science Foundation of China Contract grant number: 21306048

语种：英文

外文关键词：Zymomonas mobilis; tolerance; phenolic inhibitors; lignocellulose; corncob residue; ethanol fermentation

摘要：Corncob residue as the lignocellulosic biomass accumulated phenolic compounds generated from xylitol production industry. For utilization of this biomass, Zymomonas mobilis ZM4 was tested as the ethanol fermenting strain and presented a better performance of cell growth (2.8x10(8)CFU/mL) and ethanol fermentability (54.42g/L) in the simultaneous saccharification and fermentation (SSF) than the typical robust strain Saccharomyces cerevisiae DQ1 (cell growth of 2.9x10(7)CFU/mL, ethanol titer of 48.6g/L). The physiological response of Z. mobilis ZM4 to the twelve typical phenolic compounds derived from lignocellulose was assayed and compared with that of S. cerevisiae DQ1. Z. mobilis ZM4 showed nearly the same tolerance to the phenolic aldehydes with S. cerevisiae DQ1, but the stronger tolerance to the phenolic acids existing in corncob residue (2-furoic acid, p-hydroxybenzoic acid, p-coumaric acid, vanillic acid, ferulic acid, and syringic acid). The tolerance mechanism of Z. mobilis was investigated in terms of inhibitor degradation, cell morphology and membrane permeability under the stress of phenolics using GC-MS, scanning and transmission electron microscopies (SEM and TEM), as well as fluorescent probes. The results reveal that Z. mobilis ZM4 has the capability for in situ detoxification of phenolic aldehydes, and the lipopolysaccharide aggregation on the cell outer membrane of Z. mobilis ZM4 provided the permeable barrier to the attack of phenolic acids. Biotechnol. Bioeng. 2015;112: 1770-1782. (c) 2015 Wiley Periodicals, Inc.