Sludge morphology considerably affects the mechanism underlying microbial anaerobic degradation of phenol. Here, we assessed the phenol degradation rate, specific methanogenic activity, electron transport activity, coenzyme F420 concentration, and microbial community structure of five phenol-degrading sludge of varying particle sizes (i.e., < 20, 20-50, 50-100, 100-200, and > 200 μm). The results indicated an increase in phenol degradation rate and microbial community structure that distinctly correlated with an increase in sludge particle size. Although the sludge with the smallest particle size (< 20 μm) showed the lowest phenol degradation rate (9.3 mg COD·gVSS-1 day-1), its methanogenic activity with propionic acid, butyric acid, and H2/CO2 as substrates was the best, and the concentration of coenzyme F420 was the highest. The small particle size sludge did not contain abundant syntrophic bacteria or hydrogenotrophic methanogens, but contained abundant acetoclastic methanogens. Moreover, the floc sizes of the different sludge varied in important phenol-degrading bacteria and archaea, which may dominate the synergistic mechanism. This study provides a new perspective on the role of sludge floc size on the anaerobic digestion of phenol.

中文翻译：

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粒径分布对苯酚厌氧降解的影响及产甲烷微生物群落分析。

污泥的形态极大地影响了微生物苯酚厌氧降解的机理。在这里，我们评估了五种不同粒径（即，<20、20-50、50-100、100， -200，并且> 200μm）。结果表明，苯酚降解速率和微生物群落结构的增加与污泥粒径的增加明显相关。尽管最小粒径（<20μm）的污泥显示出最低的苯酚降解速率（9.3 mg COD·gVSS-1 day-1），但其以丙酸，丁酸和H2 / CO2为底物的产甲烷活性为。最佳，而辅酶F420的浓度最高。小颗粒污泥不包含丰富的营养细菌或氢营养的产甲烷菌，但包含大量的碎裂产甲烷菌。此外，在重要的苯酚降解细菌和古细菌中，不同污泥的絮凝物大小各不相同，这可能主导了协同机制。这项研究提供了污泥絮体大小在厌氧消化苯酚中的作用的新观点。