Production of lactic acid using a new homofermentative Enterococcus faecalis isolate

Area of Science:

• Biotechnology
• Industrial Microbiology
• Chemical Engineering

Background:

• Lactic acid is a key chemical with diverse applications in food, pharmaceuticals, and cosmetics.
• Current industrial production methods for lactic acid face challenges in cost-efficiency and optimization.
• Continuous improvement in lactic acid production parameters is crucial for industrial advancements.

Purpose of the Study:

• To describe the production of lactic acid at high concentration, yield, and volumetric productivity.
• To utilize a novel homofermentative, facultative anaerobe, Enterococcus faecalis CBRD01, for enhanced lactic acid synthesis.
• To explore optimized fermentation parameters for cost-effective lactic acid manufacturing.

Main Methods:

• Fed-batch fermentation of glucose using Enterococcus faecalis CBRD01.
• Cultivation under controlled conditions to maximize lactic acid yield and productivity.
• Analysis of carbon conversion efficiency and metabolite purity.

Main Results:

• Achieved a maximum lactic acid concentration of 182 g/l after 38 hours of fermentation.
• Demonstrated high carbon conversion efficiency, with 87-98% of carbon converted to lactic acid.
• Reported an overall volumetric productivity of 5 g/l/h, with a peak productivity of 10.3 g/l/h at 13 hours.
• Produced lactic acid with high purity, with other metabolites below 0.1%.

Conclusions:

• Enterococcus faecalis CBRD01 enables enhanced lactic acid production with superior concentration and volumetric productivity.
• The high purity of the produced lactic acid suggests reduced downstream purification costs.
• This study presents a promising opportunity for more efficient and cost-effective industrial lactic acid manufacturing.