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Indexed by:期刊论文

Date of Publication:2018-01-01

Journal:Bioprocess and biosystems engineering

Included Journals:PubMed、SCIE

Volume:41

Issue:8

Page Number:1079-1088

ISSN No.:1615-7605

Key Words:1,3-Propanediol; Microbial consortium; Ionic liquids; Crude glycerol

Abstract:Ionic liquids (ILs) as "green" solvents have been widely used owing to their excellent properties, e.g., for biodiesel production. Crude glycerol as a by-product in biodiesel production is an ideal feedstock for the microbial production of 1,3-propanediol (PDO), which is a versatile bulk chemical. PDO can be produced by microbial consortium with the advantages of high substrate tolerance and narrow by-product profile. In the present study, the effect of IL 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([Emim][TfO]) was evaluated on the capacity of PDO production from crude glycerol by microbial consortium DL38-BH. In the batch fermentation at 60g/L crude glycerol and 10g/L [Emim][TfO], the concentration and yield of PDO from glycerol increased from 23.14g/L and 0.45mol/mol to 31.17g/L and 0.60mol/mol, respectively. Our results showed that [Emim][TfO] decreased the ratio of intracellular NADH to NAD+ and increased the concentration of 3-HPA during batch fermentation. The activities of three key enzymes in glycerol metabolism were stimulated by [Emim][TfO] during the batch fermentation by microbial consortium DL38-BH. Compared to the control, the proportion of Klebsiella genus which could convert glycerol to PDO increased significantly from 79.19% to 89.49% and the other genera that did not produce PDO were dramatically decreased (P<0.05) at the end of batch fermentation. This work demonstrated that [Emim][TfO] significantly improved the concentration and yield of PDO from crude glycerol by adjusting microbial community during batch fermentation by microbial consortium.