Comparison of indigenous and exogenous microbiota: necessity of inoculation for lactic acid production

作者：Yuan Li, Yueji Chen, Zongmin Du, Jinling He, Yurong Zhang, Yonghong Ma, Shuanglan Cheng, Xianbao Xu, Wenjuan Zhang, Zhang Ai, Xiang Li, Xu Duan, Gang Xue, Jacek Mąkinia · 发表于：Bioresource Technology · 年份：2025 · DOI：10.1016/j.biortech.2025.133439 · 被引用次数：3 · 研究领域：Probiotics and Fermented Foods、Microbial Metabolites in Food Biotechnology、Anaerobic Digestion and Biogas Production

• Anaerobic sludge (AS) inoculation produced 34.5 ± 3.0 g COD/L lactic acid (LA). • Eggshells (EG) amendment using indigenous microorganism matched AS performance. • Optical purity of L-LA reached 76.6% using EG amendment without extra inocula. • Lactic acid bacteria were enriched (37.3%) using indigenous microorganisms. • EG efficiently enhanced the pathway of EMP, HMP, and HK for LA synthesis. Lactic acid (LA) production from food waste fermentation offers a promising route for organic waste valorization and aligns with a circular economy concept. However, the microbial metabolic interactions remain poorly understood. This study demonstrates that regulating indigenous microbiota with eggshell (EG) buffer can achieve efficient LA production (33.2 ± 2.6 g COD/L), a yield only 3.6 % lower than that obtained with anaerobic sludge inoculation. Metabolic pathway analysis indicated that EG addition not only stabilized fermentative pH but also redirected the carbon flux toward LA. High-throughput sequencing showed that homofermentative LA bacteria ( Streptococcus and Enterococcus ) accounted for 37.3 % of the microbial community under EG addition alone. Additionally, EG modulated genes in the Embden-Meyerhof-Parnas, the hexose monophosphate, and the hexokinase pathway. This study confirms that an EG-buffered fermentation system can activate indigenous microbiota for high-efficiency LA production, demonstrating that exogenous inoculation is non-essential and offering a cost-effectiv...