Beijing Key Laboratory for Source Control Technology of Water Pollution, Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
Qinglin Chuangneng (Shanghai) Technology Co., Ltd, Shanghai, 201800, China.
Environ Res. 2024 Jan 15;241:117660. doi: 10.1016/j.envres.2023.117660. Epub 2023 Nov 17.
Cow dung generates globally due to increased beef and milk consumption, but its treatment efficiency remains low. Previous studies have shown that riboflavin-loaded conductive materials can improve anaerobic digestion through enhance direct interspecies electron transfer (DIET). However, its effect on the practical anaerobic digestion of cow dung remained unclear. In this study, carbon cloth loaded with riboflavin (carbon cloth-riboflavin) was added into an anaerobic digester treating cow dung. The carbon cloth-riboflavin reactor showed a better performance than other two reactors. The metagenomic analysis revealed that Methanothrix on the surface of the carbon cloth predominantly utilized the CO reduction for methane production, further enhanced after riboflavin addition, while Methanothrix in bulk sludge were using the acetate decarboxylation pathway. Furthermore, the carbon cloth-riboflavin enriched various major methanogenic pathways and activated a large number of enzymes associated with DIET. Riboflavin's presence altered the microbial communities and the abundance of functional genes relate to DIET, ultimately leading to a better performance of anaerobic digestion for cow dung.
牛粪因牛肉和牛奶消费的增加而在全球范围内产生，但处理效率仍然很低。先前的研究表明，负载核黄素的导电材料可以通过增强直接种间电子传递（DIET）来改善厌氧消化。然而，其对牛粪实际厌氧消化的影响尚不清楚。在本研究中，将负载核黄素的碳纤维布（碳纤维布-核黄素）添加到处理牛粪的厌氧消化器中。碳纤维布-核黄素反应器的性能优于其他两个反应器。宏基因组分析表明，碳纤维布表面的甲烷丝菌主要利用 CO 还原生成甲烷，添加核黄素后进一步增强，而絮体污泥中的甲烷丝菌则利用乙酸脱羧途径。此外，碳纤维布-核黄素富集了各种主要的产甲烷途径，并激活了大量与 DIET 相关的酶。核黄素的存在改变了微生物群落和与 DIET 相关的功能基因的丰度，最终导致牛粪厌氧消化性能的提高。
