School of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China.
School of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China.
Water Res. 2022 Oct 1;224:119050. doi: 10.1016/j.watres.2022.119050. Epub 2022 Sep 3.
Saline mariculture wastewater containing multi-antibiotics poses a challenge to anaerobic ammonia oxidation (anammox) process. Herein, the halophilic marine anammox bacteria (MAB)-based microbiome was used for treating mariculture wastewater (35‰ salinity) under multi-antibiotics (enrofloxacin + oxytetracycline + sulfamethoxazole, EOS) stress. And the main focus of this study lies in the response of MAB-based microbiome against multi-antibiotics stress. It is found that MAB-based microbiome shows stable community structure and contributes high nitrogen removal efficiency (>90%) even under high stress of EOS (up to 4 mg·L). The relative abundance of main functional genus Candidatus Scalindua, responsible for anammox, had little change while controlling the influent EOS concentration within 4 mg·L, whereas, significantly decreased to 2.23% at EOS concentration of as high as 24 mg·L. As an alternative, antibiotic resistance bacteria (ARB) species Rheinheimera dominated the microbial community of MAB-based biological reactor under extremely high EOS stress (e.g. 24 mg·L in influent). The response mechanism of MAB-based microbiome consists of extracellular and intracellular defenses with dependence of EOS concentration. For example, while EOS within 4 mg·L in this study, most of the antibiotics were retained by extracellular polymeric substances (EPS) via adsorption; If increasing the EOS concentration to 8 and even 24 mg·L, part of antibiotics could intrude into the cells and cause the intracellular accumulation of antibiotic resistance genes (ARGs) (total abundance up to 2.44 × 10 copies/16S rRNA) for EOS response. These new understandings will facilitate the practical implementation of MAB-based bioprocess for saline nitrogen- and antibiotics-laden wastewater treatment.
含多种抗生素的海水养殖废水对厌氧氨氧化（anammox）过程构成挑战。在此，采用嗜盐海洋厌氧氨氧化菌（MAB）为基础的微生物组处理海水养殖废水（盐度 35‰），并在多种抗生素（恩诺沙星+土霉素+磺胺甲恶唑，EOS）压力下运行。本研究的主要重点是 MAB 为基础的微生物组对多种抗生素压力的响应。结果发现，即使在高 EOS（高达 4 mg·L）压力下，MAB 为基础的微生物组仍表现出稳定的群落结构和高氮去除效率（>90%）。负责 anammox 的主要功能属 Candidatus Scalindua 的相对丰度在控制进水 EOS 浓度在 4 mg·L 以内时几乎没有变化，而在 EOS 浓度高达 24 mg·L 时，其相对丰度显著下降至 2.23%。作为替代，在极高 EOS 压力（例如进水 24 mg·L）下，抗生素抗性细菌（ARB）种莱茵海默氏菌（Rheinheimera）主导了 MAB 为基础生物反应器的微生物群落。MAB 为基础的微生物组的响应机制包括细胞外和细胞内防御，取决于 EOS 浓度。例如，在本研究中，当 EOS 浓度在 4 mg·L 以内时，大多数抗生素通过吸附被细胞外聚合物物质（EPS）保留；如果将 EOS 浓度增加到 8 甚至 24 mg·L，则部分抗生素可能会侵入细胞，导致抗生素抗性基因（ARGs）的细胞内积累（总量高达 2.44×10 拷贝/16S rRNA）以应对 EOS。这些新的认识将有助于 MAB 为基础的生物工艺在处理含盐含氮和含抗生素废水方面的实际应用。
