Syngas biomethanation is an attractive process for extending application of gasification products. In the present study, anaerobic sludges from three methanogenic reactors feeding cattle manure (CS), sewage sludge (SS) and gaseous H₂/CO₂ (GS) were used to investigate the effect of microbial consortia composition on syngas biomethanation. The results showed that CS presented the highest CO consumption rate due to its highest relative abundance of CO consuming bacteria. The CO was mainly converted to acetate, and syntrophic acetate oxidization (SAO) bacteria converted acetate to H₂/CO₂ for hydrogenotrophic methanogenesis in CS and SS. However, acetate was accumulated in GS for lacking acetoclastic methanogens and SAO bacteria, leading to lower biomethanation efficiency. Additionally, adding stoichiometric H₂ could convert CO and CO₂ to nearly pure methane, while, the CO consumption rate declined in H₂ added systems. The results present novel insights into microbial consortia on CO conversion and syngas biomethanation.

合成气生物甲烷化是吸引气化产品应用的有吸引力的方法。在本研究中，使用来自三个饲喂牛粪（CS），污水污泥（SS）和气态H ₂ / CO ₂（GS）的产甲烷反应器的厌氧污泥来研究微生物群落组成对合成气生物甲烷化的影响。结果表明，由于CS消耗细菌的相对丰度最高，因此CS表现出最高的CO消耗率。CO主要转化为乙酸盐，而腐殖酸乙酸氧化（SAO）细菌将乙酸盐转化为H ₂ / CO ₂在CS和SS中的氢营养性甲烷生成。但是，由于缺乏破骨细胞产甲烷菌和SAO细菌，乙酸盐在GS中积累，导致生物甲烷化效率降低。另外，添加化学计量的H ₂可以将CO和CO ₂转化为几乎纯净的甲烷，而在添加H _2的系统中，CO的消耗率下降。结果提供了有关CO转化和合成气生物甲烷化的微生物联盟的新见解。