Efficient production of lactic acid from cellulose and xylan in sugarcane bagasse by newly isolated Lactiplantibacillus plantarum and Levilactobacillus brevis through simultaneous saccharification and co-fermentation process

Chularat Haokok; Siriporn Lunprom; Alissara Reungsang; Apilak Salakkam

doi:10.1016/j.heliyon.2023.e17935

Efficient production of lactic acid from cellulose and xylan in sugarcane bagasse by newly isolated Lactiplantibacillus plantarum and Levilactobacillus brevis through simultaneous saccharification and co-fermentation process

Heliyon. 2023 Jul 4;9(7):e17935. doi: 10.1016/j.heliyon.2023.e17935. eCollection 2023 Jul.

Authors

Chularat Haokok^{1

2}, Siriporn Lunprom^{1

2}, Alissara Reungsang^{1

2

3}, Apilak Salakkam^{1

2}

Affiliations

¹ Department of Biotechnology, Faculty of Technology, Khon Kaen University, Khon Kaen, 40002, Thailand.
² Research Group for Development of Microbial Hydrogen Production Process from Biomass, Khon Kaen University, Khon Kaen, 40002, Thailand.
³ Academy of Science, Royal Society of Thailand, Bangkok, 10300, Thailand.

Abstract

Sugarcane bagasse is one of the promising lignocellulosic feedstocks for bio-based chemicals production. However, to date, most research focuses mainly on the cellulose conversion process, while hemicellulose remains largely underutilized. The conversion of glucose and xylose derived from lignocellulosic biomass can be a promising strategy to improve utilization efficiencies of resources, energy, and water, and at the same time reduce wastes generated from the process. Here, attempts were made to convert cellulose and xylan in sugarcane bagasse (SB) into lactic acid (LA) through a pre-hydrolysis and simultaneous saccharification and co-fermentation (SScF) process using newly isolated Lactiplantibacillus plantarum TSKKU P-8 and Levilactobacillus brevis CHKKU N-6. The process yielded 91.9 g/L of LA, with a volumetric productivity of 0.85 g/(L·h). This was equivalent to 137.8 ± 3.4 g-LA, a yield on substrate (pretreated SB) of 0.86 g/g, and a productivity of 1.28 g/h, based on a final volume of 1.5 L. On the other hand, pre-hydrolysis and simultaneous saccharification and fermentation (SSF) process using La. plantarum TSKKU P-8 as a monoculture gave 86.7 ± 0.2 g/L of LA and a volumetric productivity of 0.8 g/(L·h), which were equivalent to 104.8 ± 0.3 g-LA, a yield on substrate of 0.65 g/g, and a productivity of 0.97 g/h, based on a final volume of 1.2 L. Mass balance calculated based on mass of raw SB entering the process showed that the SScF process improved the product yield by 32% as compared with SSF process, resulting in 14% improvement in medium-based economic yield.

Keywords: Co-fermentation; Lactic acid; Lactiplantibacillus plantarum; Levilactobacillus brevis; Simultaneous saccharification and fermentation; Sugarcane bagasse.