Pan Xin-Rong, Shang-Guan Pei-Ken, Li Shu-Hui, Zhang Chu-Hao, Lou Jia-Min, Guo Liang, Liu Lu, Lu Yin
College of Biology and Environmental Engineering, Zhejiang Shuren University, Hangzhou, 310015, PR China.
College of Materials Science and Engineering, Chongqing University, Chongqing, 400044, PR China.
Environ Res. 2025 Feb 15;267:120645. doi: 10.1016/j.envres.2024.120645. Epub 2024 Dec 16.
Food waste is a major problem faced by human beings. Acidogenic fermentation is an effective and feasible technology for resource recovery from food waste. The mixture of volatile fatty acids (VFAs) hinders the utilization of fermentation products. In this study, we constructed fermentation reactors for food waste treatment. The operation period was separated to three stages: Stage 1 (from day 1-102), Stage 2 (from day 103-208), and Stage 3 (from day 209-304). CO was sparged to the reactors to promote the acetate enrichment at Stage 3. Bioinformatics analysis were performed to analyze the microbial community, genes, and pathways. Results showed that the highest average concentration of acetate was 6044 mg-COD/L (R1) and 5000 mg-COD/L (R2) at Stage 3, which was corresponded to the stage with highest acetate ratio (63% and 66% in R1 and R2). But the highest total VFAs concentration was 39424 mg-COD/L at Stage 2. Aeriscardovia belonging to Actinobacteria had an average relative abundance of 85.7% after CO sparging. Compared with Stage 1 and Stage 2, the number of down-regulated genes and pathways at Stage 3 were much higher than the number of up-regulated genes and pathways. The significant down-regulated genes were wcaB and ttrC, and the significant down-regulated pathways were pyruvate fermentation to acetone and acetyl-CoA fermentation to butanoate II pathway. This study demonstrated that CO can promote the acetate enrichment during food waste fermentation. The main mechanism was enriching acetate fermentation microorganisms and inhibiting the interfere genes and pathways.
食物浪费是人类面临的一个主要问题。产酸发酵是一种从食物垃圾中回收资源的有效且可行的技术。挥发性脂肪酸（VFAs）混合物会阻碍发酵产物的利用。在本研究中，我们构建了用于食物垃圾处理的发酵反应器。运行期分为三个阶段：第1阶段（第1 - 102天）、第2阶段（第103 - 208天）和第3阶段（第209 - 304天）。在第3阶段向反应器中通入CO以促进乙酸盐富集。进行了生物信息学分析以分析微生物群落、基因和途径。结果表明，第3阶段乙酸盐的最高平均浓度在R1中为6044 mg-COD/L，在R2中为5000 mg-COD/L，这与乙酸盐比例最高的阶段相对应（R1和R2中分别为63%和66%）。但第2阶段总VFAs浓度最高，为39424 mg-COD/L。属于放线菌的气胞菌在通入CO后平均相对丰度为85.7%。与第1阶段和第2阶段相比，第3阶段下调的基因和途径数量远高于上调的基因和途径数量。显著下调的基因是wcaB和ttrC，显著下调的途径是丙酮酸发酵生成丙酮和乙酰辅酶A发酵生成丁酸II途径。本研究表明，CO可促进食物垃圾发酵过程中的乙酸盐富集。主要机制是富集乙酸盐发酵微生物并抑制干扰基因和途径。
