title: Efficient bioconversion of 2,3-butanediol into acetoin using Gluconobacter oxydans DSM 2003.
abstract: BACKGROUND
  2,3-Butanediol is a platform and fuel biochemical that can be efficiently produced from biomass. However, a value-added process for this chemical has not yet been developed. To expand the utilization of 2,3-butanediol produced from biomass, an improved derivative process of 2,3-butanediol is desirable.
  
  
  RESULTS
  In this study, a Gluconobacter oxydans strain DSM 2003 was found to have the ability to transform 2,3-butanediol into acetoin, a high value feedstock that can be widely used in dairy and cosmetic products, and chemical synthesis. All three stereoisomers, meso-2,3-butanediol, (2R,3R)-2,3-butanediol, and (2S,3S)-2,3-butanediol, could be transformed into acetoin by the strain. After optimization of the bioconversion conditions, the optimum growth temperature for acetoin production by strain DSM 2003 was found to be 30°C and the medium pH was 6.0. With an initial 2,3-butanediol concentration of 40 g/L, acetoin at a high concentration of 89.2 g/L was obtained from 2,3-butanediol by fed-batch bioconversion with a high productivity (1.24 g/L · h) and high yield (0.912 mol/mol).
  
  
  CONCLUSIONS
  G. oxydans DSM 2003 is the first strain that can be used in the direct production of acetoin from 2,3-butanediol. The product concentration and yield of the novel process are both new records for acetoin production. The results demonstrate that the method developed in this study could provide a promising process for efficient acetoin production and industrially produced 2,3-butanediol utilization.
authors.forename: Xiuqing
authors.initials: X
authors.lastname: Wang
authors.forename: Min
authors.initials: M
authors.lastname: Lv
authors.forename: Lijie
authors.initials: L
authors.lastname: Zhang
authors.forename: Kun
authors.initials: K
authors.lastname: Li
authors.affiliation: State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, People's Republic of China. jieerbu@sdu.edu.cn.
authors.forename: Chao
authors.initials: C
authors.lastname: Gao
authors.forename: Cuiqing
authors.initials: C
authors.lastname: Ma
authors.forename: Ping
authors.initials: P
authors.lastname: Xu