title: High-purity propionate production from glycerol in mixed culture fermentation.
abstract: High-purity propionate production from glycerol in mixed culture fermentation (MCF) induced by high ammonium concentration was investigated. Fed-batch experiments revealed that higher ammonium concentration (>2.9g/L) had simultaneous negative effects on acetate and propionate degradation. Propionate production and yield was up to 22.6g/L and 0.45g COD/g COD glycerol, respectively, with a purity of 96%. Sequential batch experiments demonstrated that the yields of propionate were 0.3±0.05, 0.32±0.01, and 0.34±0.03g COD/g COD at a glycerol concentration of 2.78, 4.38, and 5.56g/L, respectively, and the purity of propionate was 91-100%. Microbial community analysis showed that the phylum Firmicutes dominated the bacterial community at different glycerol concentrations. However, the Methanosaeta population decreased from 46% to 6% when glycerol concentration increased from 2.78 to 5.56g/L, resulting in lower acetate degradation rate. Thus, the present study might provide an alternative option for the production of propionate from glycerol via MCF.
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Chen
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
authors.forename: Ting
authors.initials: T
authors.lastname: Wang
authors.affiliation: School of Environmental Engineering and Science, Yangzhou University, 196 West Huayang Road, Yangzhou, Jiangsu 225127, People's Republic of China.
authors.forename: Nan
authors.initials: N
authors.lastname: Shen
authors.affiliation: Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, Hebei 066004, People's Republic of China.
authors.forename: Fang
authors.initials: F
authors.lastname: Zhang
authors.affiliation: CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China; Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou, Jiangsu 215123, People's Republic of China. Electronic address: rzeng@ustc.edu.cn.
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Zeng
mesh_terms: D000085:Acetates / Q000378:metabolism; D064751:Ammonium Compounds; D019149:Bioreactors / Q000382:microbiology*; D005285:Fermentation; D005990:Glycerol / Q000378:metabolism*; D059013:Microbial Consortia; D011422:Propionates / Q000378:metabolism*
chemical_list: D000085:Acetates; D064751:Ammonium Compounds; D011422:Propionates; D005990:Glycerol
keywords: Ammonium; Glycerol; High purity; Mixed culture fermentation; Propionate