Abstract：
Ofloxacin (OFL) is a commonly used antibiotic that can enter wastewater treatment plants and be adsorbed by the sludge, resulting in a high OFL concentration in sludge and affecting the subsequent sludge anaerobic digestion process. However, the micro mechanisms involved in this process have not been thoroughly studied. Therefore, this study focuses on the effect of OFL on the sludge anaerobic digestion of sludge to provide such support. The experimental results showed that the maximal methane yield decreased from 277.7 to 164.7 mL/g VSS with the OFL concentration increased from 0 to 300 mg/L. Additionally, OFL hindered the intermediate biochemical processes of hydrolysis, acidogenesis, acetogenesis, and acetoclastic methanogenesis. However, it promoted hydrogenotrophic methanogenesis process, using H2 as substrate, with the concentration of 300 mg/L OFL was 5.54 fold methane production of that in the control. Further investigation revealed that the negative effect of OFL was likely due to the induction of reactive oxygen species, which led to a decrease in cell activity and interference with the activity of key enzymes. Microbiological analysis revealed that OFL reduced the relative abundance of hydrolysis and acidogenesis bacteria, and Methanosaeta archaea, while increasing the relative abundance of hydrogenotrophic methanogenesis microorganism from 36.54% to 51.48% as the OFL concentration increase from 0 to 300 mg/L.
摘要：
氧氟沙星（OFL）是一种常用的抗生素，可以进入污水处理厂并被污泥吸附，导致污泥中OFL浓度高，影响后续污泥厌氧消化过程。然而,参与这一过程的微观机制尚未得到彻底研究。因此,本研究为OFL对污泥厌氧消化的影响提供支持。实验结果表明，随着OFL浓度从0增加到300mg/L，最大甲烷产率从277.7降低到164.7mL/gVSS。此外,OFL阻碍了水解的中间生化过程，酸发生，乙酸生成,和乙酸碎屑甲烷生成。然而,它促进了氢营养甲烷生成过程，使用H2作为底物，浓度为300mg/L的OFL是对照的5.54倍。进一步的研究表明，OFL的负面影响可能是由于活性氧的诱导，这导致细胞活性降低并干扰关键酶的活性。微生物学分析表明，OFL降低了水解和产酸细菌的相对丰度，和甲烷古细菌，随着OFL浓度从0增加到300mg/L，氢营养型产甲烷微生物的相对丰度从36.54％增加到51.48％。
