Continuous fermentation using high cell density cell recycle system for L-lactic acid production

Abstract

For complete utilization of high glucose at ∼100 g/L, a high cell density (HCD) continuous fermentation system was established using Lb. delbrueckii NCIM 2025 for the bioproduction of lactic acid (LA). An integrated membrane cell recycling system coupled with the continuous bioreactor, aided to achieve the highest 34.77 g/L h LA productivity and 0.94−0.98 g/g yield. ∼34 times higher productivity was observed (in comparison to batch fermentation conducted in this study), when the continuous operations were carried out at the maximum dilution rate and wet cell weight i.e. 0.36 h⁻¹ and 230 g/L, respectively. These results show the potential of this method for large-scale lactic acid production because it not only produces high titers but also ensures that glucose is used effectively. The method’s superior performance in comparison to earlier studies suggests it as an affordable and sustainable alternative for the production of LA.

Keywords:

• Lactic acid
• continuous fermentation
• high cell density
• cell recycle
• yield
• productivity
• glucose

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was financially supported by the Implementation of the “DBT-ICT Centre for Energy Biosciences Phase II-BT/EB/ICT-Extension 2012, 05.06.2013”.