In this study, the YH consortium, an ethene-producing culture, was used to evaluate the effect of vitamin B₁₂ (VB₁₂) on trichloroethene (TCE) dechlorination by transferring the original TCE-reducing culture with or without adding exogenous VB₁₂. Ultra-high performance liquid chromatography - tandem mass spectrometry (UPLC-MS/MS) was applied to detect the concentrations of VB₁₂ and its lower ligand 5,6-dimethylbenzimidazole (DMB) in the cultures. After three successive VB₁₂ starvation cycles, the dechlorination of TCE stopped mostly at cis-dichloroethene (cDCE), and no ethene was found; methane production increased significantly, and no VB₁₂ was detected. Results suggest that the co-cultured microbes may not be able to provide enough VB₁₂ as a cofactor for the growth of Dehalococcoides in the YH culture, possibly due to the competition for corrinoids between Dehalococcoides and methanogens. The relative abundances of 16 S rRNA gene of Dehalococcoides and reductive dehalogenase genes tceA or vcrA were lower in the cultures without VB₁₂ compared with the cultures with VB₁₂. VB₁₂ limitation changed the microbial community structures of the consortia. In the absence of VB₁₂, the microbial community shifted from dominance of Chloroflexi to Proteobacteria after three consecutive VB₁₂ starvation cycles, and the dechlorinating genus Dehalococcoides declined from 42.9% to 13.5%. In addition, Geobacter, Clostridium, and Desulfovibrio were also present in the cultures without VB₁₂. Furthermore, the abundance of archaea increased under VB₁₂ limited conditions. Methanobacterium and Methanosarcina were the predominant archaea in the culture without VB₁₂.

在这项研究中，YH财团（一种产乙烯的培养物）被用于评估维生素B ₁₂（VB ₁₂）对三氯乙烯（TCE）脱氯的作用，方法是转移有或没有添加外源VB ₁₂的原始降低TCE的培养物。应用超高效液相色谱-串联质谱法（UPLC-MS / MS）检测培养物中VB ₁₂及其较低配体5,6-二甲基苯并咪唑（DMB）的浓度。在连续三个VB ₁₂饥饿周期后，TCE的脱氯大部分在顺式-二氯乙烯（cDCE）处停止，没有发现乙烯。甲烷产量显着增加，并且没有VB ₁₂被检测到。结果表明，共培养的微生物可能无法提供足够的VB ₁₂作为YH培养物中Dehaloccocoides生长的辅助因子，这可能是由于Dehaloccocoides与产甲烷菌之间存在类固醇竞争所致。第16号第rRNA基因的相对丰度Dehalococcoides和还原性脱卤素基因TCEA或vcrA而不VB分别在培养物中低₁₂与VB培养物相比，₁₂。VB _12的限制改变了联盟的微生物群落结构。在没有VB ₁₂的情况下，连续三个VB ₁₂饥饿周期后，微生物群落从支气管弯曲菌转移到了变形杆菌，脱卤球藻的脱氯菌种从42.9％下降到13.5％。此外，在不含VB ₁₂的培养物中也存在Geobacter，Clostridium和Desulfovibrio。此外，在VB ₁₂受限条件下，古细菌的丰度增加。甲烷杆菌和甲烷菌是无VB ₁₂培养中的主要古细菌。