title: Open fermentative production of fuel ethanol from food waste by an acid-tolerant mutant strain of Zymomonas mobilis.
abstract: The aim of present study was to develop a process for open ethanol fermentation from food waste using an acid-tolerant mutant of Zymomonas mobilis (ZMA7-2). The mutant showed strong tolerance to acid condition of food waste hydrolysate and high ethanol production performance. By optimizing fermentation parameters, ethanol fermentation with initial glucose concentration of 200 g/L, pH value around 4.0, inoculum size of 10% and without nutrient addition was considered as best conditions. Moreover, the potential of bench scales fermentation and cell reusability was also examined. The fermentation in bench scales (44 h) was faster than flask scale (48 h), and the maximum ethanol concentration and ethanol yield (99.78 g/L, 0.50 g/g) higher than that of flask scale (98.31 g/L, 0.49 g/g). In addition, the stable cell growth and ethanol production profile in five cycles successive fermentation was observed, indicating the mutant was suitable for industrial ethanol production.
authors.affiliation: College of Environmental and Chemical Engineering, Dalian University, Dalian 116622, PR China.
authors.forename: Kedong
authors.initials: K
authors.lastname: Ma
authors.affiliation: Key Laboratory of Microbial Resources (Ministry of Agriculture, China), Institute of Agricultural Resources and Regional Planning, CAAS, Beijing 100081, PR China.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Ruan
authors.affiliation: Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture, Biomass Energy Technology Research Centre, Biogas Institute of Ministry of Agriculture, Chengdu 610041, PR China.
authors.forename: Zongxia
authors.initials: Z
authors.lastname: Shui
authors.affiliation: Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture, Biomass Energy Technology Research Centre, Biogas Institute of Ministry of Agriculture, Chengdu 610041, PR China.
authors.forename: Yanwei
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture, Biomass Energy Technology Research Centre, Biogas Institute of Ministry of Agriculture, Chengdu 610041, PR China.
authors.forename: Guoquan
authors.initials: G
authors.lastname: Hu
authors.affiliation: Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture, Biomass Energy Technology Research Centre, Biogas Institute of Ministry of Agriculture, Chengdu 610041, PR China. Electronic address: hemingxiong@caas.cn.
authors.forename: Mingxiong
authors.initials: M
authors.lastname: He
mesh_terms: D003246:Conservation of Energy Resources / Q000379:methods; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D005502:Food; D005947:Glucose / Q000378:metabolism; D012037:Refuse Disposal / Q000379:methods*; D017355:Zymomonas / Q000235:genetics / Q000378:metabolism*
chemical_list: D000431:Ethanol; D005947:Glucose
keywords: Acid-tolerant mutant; Food waste; Fuel ethanol; Open fermentation; Zymomonas mobilis