Predominant Contribution of Syntrophic Acetate Oxidation to Thermophilic Methane Formation at High Acetate Concentrations
Predominant Contribution of Syntrophic Acetate Oxidation to Thermophilic Methane Formation at High Acetate Concentrations
复制标题
高乙酸浓度下互养乙酸氧化对嗜热甲烷形成的主要贡献
DOI：
10.1021/es102228v
复制
发表时间：
2011-01-15
影响因子：
11.4
通讯作者：
Shao, Li-Ming
中科院分区：
文献类型：
--
作者：
Hao, Li-Ping;Lue, Fan;Shao, Li-Ming
为定量研究酸化胁迫条件下互养型乙酸盐氧化对高温厌氧产甲烷的贡献，采用同位素示踪和选择性抑制技术，结合不可培养微生物分析，对100 mmol/L乙酸盐的产甲烷转化过程进行了同步监测.这两种定量方法表明，在存在的aceticarbital和氢营养产甲烷菌，甲烷的大比例（高达89%）最初来自CO2还原，表明在高酸浓度的互养乙酸盐氧化途径的乙酸盐降解的主要贡献。氢营养产甲烷的分数从超过60%到小于40%的时间减少反映了乙酸盐产甲烷途径的逐渐流行沿着乙酸盐的减少。乙酸甲烷化途径的这种明显的歧视突出了互养乙酸氧化细菌从高有机负荷初始化产甲烷的重要性。
To quantify the contribution of syntrophic acetate oxidation to thermophilic anaerobic methanogenesis under the stressed condition induced by acidification, the methanogenic conversion process of 100 mmol/L acetate was monitored simultaneously by using isotopic tracing and selective inhibition techniques, supplemented with the analysis of unculturable microorganisms. Both quantitative methods demonstrated that, in the presence of aceticlastic and hydrogenotrophic methanogens, a large percentage of methane (up to 89%) was initially derived from CO2 reduction, indicating the predominant contribution of the syntrophic acetate oxidation pathway to acetate degradation at high acid concentrations. A temporal decrease of the fraction of hydrogenotrophic methanogenesis from more than 60% to less than 40% reflected the gradual prevalence of the aceticlastic methanogenesis pathway along with the reduction of acetate. This apparent discrimination of acetate methanization pathways highlighted the importance of the syntrophic acetate-oxidizing bacteria to initialize methanogenesis from high organic loadings.