title: The implementation of high fermentative 2,3-butanediol production from xylose by simultaneous additions of yeast extract, Na2EDTA, and acetic acid.
abstract: The effective use of xylose may significantly enhance the feasibility of using lignocellulosic hydrolysate to produce 2,3-butanediol (2,3-BD). Previous difficulties in 2,3-BD production include that the high-concentration xylose cannot be converted completely and the fermentation rate is slow. This study investigated the effects of yeast extract, ethylenediaminetetraacetic acid disodium salt (Na2EDTA), and acetic acid on 2,3-BD production from xylose. The central composite design approach was used to optimize the concentrations of these components. It was found that simultaneous addition of yeast extract, Na2EDTA, and acetic acid could significantly improve 2,3-BD production. The optimal concentrations of yeast extract, Na2EDTA, and acetic acid were 35.2, 1.2, and 4.5 g/L, respectively. The 2,3-BD concentration in the optimized medium reached 39.7 g/L after 48 hours of shake flask fermentation, the highest value ever reported in such a short period. The xylose utilization ratio and the 2,3-BD concentration increased to 99.0% and 42.7 g/L, respectively, after 48 hours of stirred batch fermentation. Furthermore, the 2,3-BD yield was 0.475 g/g, 95.0% of the theoretical maximum value. As the major components of lignocellulosic hydrolysate are glucose, xylose, and acetic acid, the results of this study indicate the possibility of directly using the hydrolysate to effectively produce 2,3-BD.
authors.affiliation: Environmental Simulation and Pollution Control State Key Joint Laboratory, School of Environment, Tsinghua University, Beijing 100084, PR China. Electronic address: lzsx1991@qq.com.
authors.forename: Xiao-Xiong
authors.initials: XX
authors.lastname: Wang
authors.affiliation: Environmental Simulation and Pollution Control State Key Joint Laboratory, School of Environment, Tsinghua University, Beijing 100084, PR China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, PR China.
authors.forename: Hong-Ying
authors.initials: HY
authors.lastname: Hu
authors.affiliation: Department of Chemical Engineering, Tsinghua University, Beijing 100084, PR China.
authors.forename: De-Hua
authors.initials: DH
authors.lastname: Liu
authors.affiliation: Department of Chemical Engineering, Tsinghua University, Beijing 100084, PR China.
authors.forename: Yuan-Quan
authors.initials: YQ
authors.lastname: Song
mesh_terms: D019342:Acetic Acid / Q000494:pharmacology*; D061249:Batch Cell Culture Techniques; D019149:Bioreactors / Q000382:microbiology; D002072:Butylene Glycols / Q000378:metabolism*; D003470:Culture Media / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology*; D005285:Fermentation / Q000187:drug effects*; D007709:Klebsiella / Q000187:drug effects / Q000378:metabolism; D015203:Reproducibility of Results; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D014994:Xylose / Q000378:metabolism*
chemical_list: D002072:Butylene Glycols; D003470:Culture Media; C026978:2,3-butylene glycol; D004492:Edetic Acid; D014994:Xylose; D019342:Acetic Acid