Bioconversion of industrial glycerol on liquid medium with culture of Lactobacillus brevis WLP 672 - lactic acid production

This study aimed to investigate the effect of glycerol concentration on the lactic acid yield of Lactobacillus brevis. Results indicate that the strain efficiently produces lactic acid, achieving a maximum concentration of 2.5 g/L after 48 h of fermentation in a glycerol-supplemented medium. These findings are competitive with other microbial systems, such as Lactobacillus rhamnosus, which has shown similar yields under different conditions. The study also emphasizes the role of fermentation optimization, including glycerol fraction adjustments and enhanced monitoring techniques like UV–Vis spectroscopy and microscopy for culture analysis. L. brevis WLP 672 demonstrates significant potential for converting industrial glycerol, a biodiesel byproduct, into lactic acid under optimized liquid culture conditions.

This research underscores the economic and environmental benefits of using biodiesel-derived glycerol as a substrate, offering a sustainable pathway for waste valorisation and circular economy integration. Future directions include metabolic engineering and co-culture strategies to enhance lactic acid productivity, aligning with industrial-scale applications. Overall, this work highlights the feasibility of microbial glycerol bioconversion as a scalable and eco-friendly solution for biotechnological and industrial advancements.