Viable strategies for enhancing acetone-butanol-ethanol production from non-detoxified switchgrass hydrolysates

Yinka Adesanya; Hasan K Atiyeh; Tinuola Olorunsogbon; Asmita Khanal; Christopher C Okonkwo; Victor C Ujor; Ajay Shah; Thaddeus C Ezeji

doi:10.1016/j.biortech.2021.126167

Viable strategies for enhancing acetone-butanol-ethanol production from non-detoxified switchgrass hydrolysates

Bioresour Technol. 2022 Jan;344(Pt A):126167. doi: 10.1016/j.biortech.2021.126167. Epub 2021 Oct 19.

Authors

Yinka Adesanya¹, Hasan K Atiyeh², Tinuola Olorunsogbon³, Asmita Khanal⁴, Christopher C Okonkwo³, Victor C Ujor⁵, Ajay Shah⁴, Thaddeus C Ezeji³

Affiliations

¹ Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK, USA.
² Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK, USA. Electronic address: hasan.atiyeh@okstate.edu.
³ Department of Animal Science, The Ohio State University, and Ohio State Agricultural Research and Development Center, Wooster, OH, USA.
⁴ Department of Food, Agricultural and Biological Engineering, The Ohio State University, Wooster, OH, USA.
⁵ Department of Food Science, University of Wisconsin-Madison, Maddison, WI, USA.

PMID: 34678446
DOI: 10.1016/j.biortech.2021.126167

Abstract

A process engineering strategy was investigated towards developing a viable scheme for effective conversion of hydrothermolysis pretreated non-detoxified switchgrass hydrolysates (SH) to acetone butanol ethanol (ABE) using a metabolically engineered strain of Clostridium beijerinckii NCIMB 8052, C. beijerinckii_AKR. The engineered strain was modified by homologous integration into the chromosome and constitutive expression of Cbei_3974, which encodes an aldo-keto reductase. Intermittent feeding strategy was employed in which fermentation was initiated with 30% of the SH and the remaining 70% SH was added when the optical density (OD_600nm) of C. beijerinckii attained 0.5. The ABE (14.9 g/L) produced from non-detoxified SH by the inhibitor-tolerant C. beijerinckii_AKR was comparable to the P2-glucose control medium (14.7 g/L). Using intermittent feeding, wildtype and C. beijerinckii_AKR produced similar amounts of ABE (about 17.5 g/L). This shows that intermittent feeding strategy and C. beijerinckii_AKR enhanced ABE fermentation and eliminated the need for SH detoxification prior to fermentation.

Keywords: ABE fermentation; Aldo-keto reductase; Clostridium beijerinckii; Intermittent feeding; Non-detoxified switchgrass hydrolysate.

MeSH terms

Acetone
Butanols
Clostridium beijerinckii*
Ethanol
Fermentation
Panicum*

Substances

Butanols
Acetone
Ethanol