Strategies for enhanced acetone-butanol-ethanol production by Clostridium beijerinckii Y10 from glucose and xylose and exploration of its physiological mechanisms

To enhance the production of butanol and its ratio to the total solvent, the impacts of exogenous amino acids supplementation on acetone-butanol-ethanol (ABE) fermentation were studied. With this effort, the highest butanol and total solvent production of 14.18 ± 0.24 g/L and 16.29 ± 0.31 g/L were achieved when 5.0 mg/L of phenylalanine was added at 18 h. Additionally, to explore the physiological reasons for the efficient synthesis of butanol under the optimal condition, the changes of key enzyme activities in the butanol synthesis pathway and the intracellular microenvironment were investigated. The findings show that phenylalanine addition could enhance crude enzyme activities of acetate kinase and butyrate kinase activities, strengthen NADH synthesis and expend more ATP to promote the growth of Clostridium beijerinckii Y10. This study suggests that the method of a tiny amount of amino acid addition was a simple and efficient approach to enhance bio-butanol production, thus providing a new strategy to improve the performance of other similar fermentation.