Kinetic modeling of substrate and product inhibition for 2,3-butanediol production by Klebsiella oxytoca

• Kinetic models were proposed to describe the production of 2,3-BD by K. oxytoca.
• The models have well elucidated the fermentative characteristics for 2,3-BD production.
• The models provide information to improve the performance of 2,3-BD production.

There has been a growing interest in the fermentative production of 2,3-butanediol (2,3-BD) because of its wide applications in the chemical, food, pharmaceutical, and fuel industries. In this study, we set up kinetic models to predict the behavior of Klebsiella oxytoca ΔldhA mutant in the batch fermentation of 2,3-BD. Modified Monod model, Luedeking-Piret model, and carbon mass balance were employed to describe the effects of substrate and end-products on cell growth, 2,3-BD production, and substrate consumption, respectively. All the parameters in the models were estimated by minimizing mean-squared errors between the model predictions and experimental data. The model predictions were in good agreement with the fermentation data. In particular, the models accurately described the inhibitory effects of by-products on the growth of K. oxytoca ΔldhA mutant as well as the production of 2,3-BD. Although the models cannot describe the complex metabolic phenomena, this paper may provide useful information for design and optimization of 2,3-BD fermentation process.