Dynamic Journal of Environmental Science and Technology
Available online at http://www.journaldynamics.org/djest
Vol.1(6), pp.43-52, August 2016
Article ID: DJEST/JDYA86910760
Copyright © 2016
Original Research Paper
Enhancement of specific butanol yield from glucose with butyrate as co-substrate by Clostridium beijerinckii NCIMB 8052
Xue Chi2, Jianzheng Li1, 2*, Philip Antwi2 and Rohit Kumar Jha2
1State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China.
2School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, China.
Corresponding Author. E-mail:firstname.lastname@example.org.
Received 28 April, 2016; Accepted 18 July, 2016;Available on-line 30 July, 2016.
Clostridum beijerinckii NCIMB 8052 with solventogenesis genes located in the chromosome has been identified as a promising strain for butanol production by acetone-butanol-ethanol (ABE) fermentation, but its specific butanol yield is not satisfactory. To enhance butanol yield from glucose with butyric acid as co-substrate, effect of concentration of glucose, butyric acid and inoculum were investigated by batch cultures of the strain, while the metabolic characteristics was discussed. It was found that the free butyric acid could be detoxified by enriching inoculum of the strain. Batch feeding of butyric acid could improve the availability of glucose and cell growth, but was less help to improve butanol yield. With 5 g/L butyric acid as the co-substrate of 30 g/L glucose and 0.59 g-dry cell/L inoculums in the culture, a butanol production of about 9.91 g/L was obtained. The specific butanol yield of 0.52 g/g by glucose consumed was the highest so far. The additional butyric acid could not only induce solventogenesis rapidly but also change the fermentation process, resulting in an accelerating formation of butanol and an enhancement of specific butanol yield.
Keywords: Clostridium beijerinckii, acetone-butanol-ethanol fermentation, co-substrate, butyric acid, specific butanol yield.