Various support carriers are used for high-density retention of methanogenic archaea in anaerobic wastewater treatment systems. Although the physicochemical properties of carrier materials and microorganisms influence the adhesion of methanogenic archaea, details about the underlying mechanism remain poorly characterized. We applied seven types of chemical surface modifications to carbon felts to clarify the adhesion properties of Methanothermobacter thermautotrophicus, a representative thermophilic hydrogenotrophic methanogen. The relationship between carrier surface properties and methanogen adhesion was evaluated. M. thermautotrophicus adhesion was significantly increased up to 2.6 times in comparison with control on carbon felts treated with NaOH, HCl, H₂SO₄, or Na₂HPO₄. Treated carbon felts showed a lower water contact angle, but no correlation between the carrier surface contact angle and methanogen adhesion was observed. On the other hand, at the surface of the carrier that showed improved adhesion of methanogens, the ratio of -COOH : -OH was 1 : 0.65. Such a ratio was not observed with treated carriers for which methanogen adhesion was not improved. Therefore, in the adhesion of M. thermautotrophicus, the functional group abundance was important as well as physical surface properties such as the hydrophobicity. Hydrogenotrophic methanogens are involved in active methanation during the startup of anaerobic digestion. Additionally, these methanogenic archaea function as methanogenic cathode catalysts. Therefore, anaerobic digestion performance will greatly improve by controlling the adhesion of hydrogenotrophic methanogens such as M. thermautotrophicus.

中文翻译：

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载体表面的官能团分布会影响甲烷嗜热杆菌自养菌的粘附。

各种支持载体用于在厌氧废水处理系统中高密度保留产甲烷古菌。尽管载体材料和微生物的物理化学性质会影响产甲烷古菌的附着力，但有关潜在机理的详细信息仍知之甚少。我们对碳毡进行了七种化学表面改性处理，以阐明甲烷嗜热菌自养营养菌（一种典型的嗜热氢营养型产甲烷菌）的粘附特性。评估了载体表面性质和甲烷菌粘附性之间的关系。与对照相比，用NaOH，HCl，H ₂处理的碳毡的热自养分枝杆菌的粘附力显着提高至2.6倍SO ₄或Na ₂ HPO ₄。处理过的碳毡表现出较低的水接触角，但未观察到载体表面接触角与产甲烷菌粘附性之间的相关性。另一方面，在显示出改善的产甲烷菌粘附性的载体表面上，-COOH∶-OH之比为1∶0.65。对于处理后的载体，未观察到这样的比例，对于这些载体而言，产甲烷菌的粘附性没有得到改善。因此，在嗜热支原体的粘附中，官能团的丰度以及疏水性等物理表面性质都很重要。氢营养型产甲烷菌在厌氧消化过程中参与了主动甲烷化。另外，这些产甲烷的古细菌起产甲烷的阴极催化剂的作用。因此，厌氧消化性能将通过控制氢营养型产甲烷菌如嗜热毁丝霉菌的粘附而大大提高。