College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
Bioresour Technol. 2014;152:420-8. doi: 10.1016/j.biortech.2013.11.012. Epub 2013 Nov 14.
Thermophilic and mesophilic anaerobic digestion reactors (TR and MR) using food waste as substrate were compared with emphasis on microbial responses to increasing organic loading rate (OLR). At OLR ranging from 1.0 to 2.5 g VS L(-1) d(-1), MR exhibited more stable performance compared to TR in terms of methane yield. Amplicons pyrosequencing results revealed the distinct microbial dynamics in the two reactors. Primarily, MR had greater richness and evenness of bacteria species. With OLR elevated, larger shifts of bacterial phylogeny were observed in MR; Methanosaeta dominated in archaeal community in MR while Methanothermobacter and Methanoculleus were favored in TR. The high functional redundancy in bacterial community integrated with acetoclastic methanogenesis in MR resulted in its better performance; whereas delicate interactions between hydrogen-producer and hydrogenotrophic methanogens in TR were much more prone to disruption. These results are conductive to understanding the microbial mechanisms of low methane yield during food waste anaerobic digestion.
采用食物垃圾作为底物的嗜热和中温厌氧消化反应器（TR 和 MR）进行了比较，重点是微生物对有机负荷率（OLR）增加的响应。在 OLR 为 1.0 至 2.5 g VS L(-1) d(-1)范围内，MR 在甲烷产量方面表现出比 TR 更稳定的性能。扩增子焦磷酸测序结果揭示了两个反应器中微生物动态的明显差异。首先，MR 具有更多的细菌物种丰富度和均匀度。随着 OLR 的升高，MR 中观察到细菌系统发育的更大变化；MR 中古菌群落以产甲烷菌属为主，而 TR 中则偏爱甲烷八叠球菌属和甲烷微菌属。MR 中细菌群落的高功能冗余与乙酸型产甲烷作用相结合，使其性能更好；而 TR 中氢产生菌和氢营养型产甲烷菌之间的精细相互作用更容易受到破坏。这些结果有助于理解食物垃圾厌氧消化过程中甲烷产量低的微生物机制。
