In the recirculating aquaculture systems, the aerobic biotreatment strategy for influent is frequently adopted to avoid poisonous byproducts produced under anaerobic conditions. However, residue antibiotics and nitrogenous compounds accumulate in mariculture wastewater and little is known about the effect of antibiotics on heterotrophic aerobic denitrification. Therefore, we designed a laboratory-scale aerobic bioreactor and investigated the effect of tetracycline (TET) on simultaneous nitrate (NO₃⁻-N), ammonium (NH₄⁺-N), nitrite (NO₂⁻-N), chemical oxygen demand (COD), and TET removal, an aerobic denitrification system feeding with 148 mg/L COD, 14 mg/L NO₃^—N, and 100–200 μg/L TET was setup. Results obtained from the study showed that the maximum removal efficiency for COD, NH₄⁺-N, NO₂⁻-N, and TET was 100%, 95.45%, 84.66%, and 70.68% respectively. Denitrifiers were inhibited by an increase in TET. In addition, TET degradation was highest in bioreactor B where it reached 70.68% possibly due to the existence of genera like Woesearchaeales, Thauera, Denitratisoma, Sulfuritalea, and Methylotenera, which were enriched by an initial TET dosage of 150 μg/L. The findings of this research indicated that heterotrophic aerobic denitrification is an efficient technology for simultaneously removing NO₃⁻-N, NH₄⁺-N, NO₂⁻-N, COD, and TET from mariculture wastewater.

中文翻译：

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四环素对异养好氧反硝化同时去除硝酸盐的影响

在循环水养殖系统中，经常采用好氧生物处理进水策略，以避免在厌氧条件下产生有毒副产物。然而，海水养殖废水中存在残留的抗生素和含氮化合物，而关于抗生素对异养好氧反硝化作用的影响知之甚少。因此，我们设计了一个实验室规模的好氧生物反应器，并研究了四环素（TET）对同时硝酸盐（NO ₃ ^- -N）、铵（NH ₄ ⁺ -N）、亚硝酸盐（NO ₂ ^- -N）、化学氧的影响。需氧量 (COD) 和 TET 去除，以 148 mg/L COD、14 mg/L NO _{3进料的好氧反硝化系统}^—N，并设置 100–200 μg/L TET。研究结果表明，COD、NH ₄ ⁺ -N、NO ₂ ^- -N和TET的最大去除效率分别为100%、95.45%、84.66%和70.68%。反硝化菌受到 TET 增加的抑制。此外，TET 降解在生物反应器 B 中最高，达到 70.68%，这可能是由于存在Woesearchaeales、Thauera、Denitratisoma、Sulfuritalea和Methylotenera等属，这些属通过 150 μg/L 的初始 TET 剂量富集。本研究结果表明异养好氧反硝化是一种同时去除NO ₃ ^- -N, NH _{4的有效技术。}⁺ -N、NO ₂ ^- -N、COD 和海水养殖废水中的 TET。