State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, PR China.
Bioresour Technol. 2013 Jul;140:319-27. doi: 10.1016/j.biortech.2013.04.113. Epub 2013 May 4.
To investigate the competition among acetate-utilizing microorganisms at different acetate levels, bioconversion processes of 50, 100, 150 and 200 mM acetate in the presence and absence of methanogenic inhibitor CH3F were monitored in thermophilic methanogenic system. The successive response of methane-producing community during the deteriorative and recovery phases caused by pH disturbance was analyzed. High acetate concentration (>50mM) inhibited the activity of acetoclastic methanogenesis (AM). The increasing pH (>7.5) enhanced this inhibition. The syntrophic acetate oxidizing (SAO) bacteria and hydrogenotrophic methanogens including Methanomicrobiales and Methanobacteirales were more tolerant to the stress from high acetate concentration and high pH. Resumption from alkali condition to normal pH stimulated the growth of acetate oxidizing syntrophs. The reaction rate of SAO-HM was lower than that of AM. These results point to the possibility to regenerate the deteriorated anaerobic digesters by addition of acclimatized inocula rich in acetate-oxidizing syntrophs.
为了研究不同乙酸水平下乙酸利用微生物之间的竞争，在存在和不存在甲烷生成抑制剂 CH3F 的情况下，监测了高温甲烷生成系统中 50、100、150 和 200 mM 乙酸的生物转化过程。分析了由于 pH 干扰导致的甲烷产生群落在恶化和恢复阶段的连续反应。高乙酸浓度（>50mM）抑制了乙酸分解产甲烷作用（AM）。较高的 pH 值（>7.5）加剧了这种抑制。产乙酸氧化菌（SAO）和包括甲烷微菌目和甲烷杆菌目在内的氢营养型产甲烷菌对高乙酸浓度和高 pH 值的应激更具耐受性。从碱性条件恢复到正常 pH 值会刺激乙酸氧化共生物的生长。SAO-HM 的反应速率低于 AM。这些结果表明，通过添加富含乙酸氧化共生物的驯化接种物，有可能使恶化的厌氧消化池得到再生。
