Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngårdsholmsvej 49, 9000 Aalborg, Denmark.
Water Res. 2015 May 15;75:312-23. doi: 10.1016/j.watres.2015.02.025. Epub 2015 Feb 25.
Anaerobic digestion is regarded as a key environmental technology in the present and future bio-based economy. The microbial community completing the anaerobic digestion process is considered complex, and several attempts already have been carried out to determine the key microbial populations. However, the key differences in the anaerobic digestion microbiomes, and the environmental/process parameters that drive these differences, remain poorly understood. In this research, we hypothesized that differences in operational parameters lead to a particular composition and organization of microbial communities in full-scale installations. A total of 38 samples were collected from 29 different full-scale anaerobic digestion installations, showing constant biogas production in function of time. Microbial community analysis was carried out by means of amplicon sequencing and real-time PCR. The bacterial community in all samples was dominated by representatives of the Firmicutes, Bacteroidetes and Proteobacteria, covering 86.1 ± 10.7% of the total bacterial community. Acetoclastic methanogenesis was dominated by Methanosaetaceae, yet, only the hydrogenotrophic Methanobacteriales correlated with biogas production, confirming their importance in high-rate anaerobic digestion systems. In-depth analysis of operational and environmental parameters and bacterial community structure indicated the presence of three potential clusters in anaerobic digestion. These clusters were determined by total ammonia concentration, free ammonia concentration and temperature, and characterized by an increased relative abundance of Bacteroidales, Clostridiales and Lactobacillales, respectively. None of the methanogenic populations, however, could be significantly attributed to any of the three clusters. Nonetheless, further experimental research will be required to validate the existence of these different clusters, and to which extent the presence of these clusters relates to stable or sub-optimal anaerobic digestion.
厌氧消化被认为是当前和未来基于生物的经济中的一项关键环境技术。完成厌氧消化过程的微生物群落被认为是复杂的，已经有几种尝试来确定关键微生物种群。然而，厌氧消化微生物组的关键差异，以及驱动这些差异的环境/过程参数，仍然知之甚少。在这项研究中，我们假设操作参数的差异导致了全规模装置中微生物群落的特定组成和组织。从 29 个不同的全规模厌氧消化装置中收集了 38 个样本，这些样本在时间上持续产生沼气。通过扩增子测序和实时 PCR 进行微生物群落分析。所有样品中的细菌群落主要由厚壁菌门、拟杆菌门和变形菌门的代表组成，占总细菌群落的 86.1±10.7%。乙酸营养型产甲烷作用主要由甲烷八叠球菌科主导，但只有产氢甲烷杆菌目与沼气产量相关，证实了它们在高速厌氧消化系统中的重要性。对操作和环境参数以及细菌群落结构的深入分析表明，厌氧消化中有三个潜在的聚类。这些聚类由总氨浓度、游离氨浓度和温度决定，分别以拟杆菌目、梭菌目和乳杆菌目相对丰度的增加为特征。然而，没有一种产甲烷种群可以明显归因于这三个聚类中的任何一个。尽管如此，仍需要进一步的实验研究来验证这些不同聚类的存在，以及这些聚类的存在与稳定或次优厌氧消化的关系。
