Engineering Lab for Water Pollution Control and Resources Recovery of Jilin Province, School of Environment, Northeast Normal University, Changchun 130117, China; School of Environment, Northeast Normal University, Changchun 130117, China.
Engineering Lab for Water Pollution Control and Resources Recovery of Jilin Province, School of Environment, Northeast Normal University, Changchun 130117, China; School of Environment, Northeast Normal University, Changchun 130117, China.
Water Res. 2023 Mar 1;231:119623. doi: 10.1016/j.watres.2023.119623. Epub 2023 Jan 17.
Storing reclaimed water via managed aquifer recharge (MAR) is an effective strategy for alleviating groundwater overdraft and achieving water resource recycling simultaneously. However, β-lactam antibiotics in the reclaimed water can induce stress on aquifer system, reshape microbial community, and affect the emergence and prevalence of antibiotic resistance genes (ARGs). In this study, three sandy soil columns (H 1.5 m, ID 14 cm) were employed to simulate MAR, and synthetic reclaimed water containing either amoxicillin (AMO), ampicillin (AMP) or oxacillin (OXA) was continuously recharged for 120 d The temporal and spatial attenuation of β-lactams and nitrogen was studied, and microbial collaboration and the resistance mechanism were elaborated. Biodegradation is the main pathway for β-lactams elimination, AMO and AMP were eliminated when migrating 30 cm, while the attenuation of OXA experienced in the whole column with final removal efficiency of 82%. Moreover, refractory OXA induced more ARGs production, and approximately 10% and 13% higher than that of AMO and AMP columns. Efflux pump and antibiotics inactivation were the two major resistance mechanisms. NO-N gradually decreased (by 26%, 38%, and 49% for AMO, AMP, and OXA, respectively) along the recharge direction. Microbial co-occurrence network revealed that nitrogen-cycling bacteria were the keystone species in aquifer community, and ammonation provided NH-N for the nitrification process of ammonia-oxidizing archaea (AOA), promoting the further denitrification for nitrogen removal in MAR process. Nitrogen-cycling bacteria were the key and active ARG hosts, which could keep nitrogen transformation activity under antibiotics stress. In sum, nitrogen-cycling bacteria exhibited intimate collaboration and elastic resistance in response to the malnutrition environment and β-lactams exposure during MAR.
通过管理型含水层补给（Managed Aquifer Recharge，MAR）来储存再生水是缓解地下水超采和实现水资源循环利用的有效策略。然而，再生水中的β-内酰胺类抗生素会对含水层系统造成压力，改变微生物群落结构，并影响抗生素抗性基因（Antibiotic Resistance Genes，ARGs）的出现和流行。本研究采用三根 1.5 米高、14 厘米内径的沙质土壤柱模拟 MAR，连续注入含有阿莫西林（Amoxicillin，AMO）、氨苄西林（Ampicillin，AMP）或苯唑西林（Oxacillin，OXA）的合成再生水 120 天，研究了β-内酰胺类抗生素和氮素的时空衰减规律，并阐述了微生物协同作用和抗性机制。生物降解是β-内酰胺类抗生素消除的主要途径，AMO 和 AMP 在迁移 30 厘米时被消除，而 OXA 的衰减则发生在整个柱中，最终去除效率为 82%。此外，难降解的 OXA 诱导产生更多的 ARGs，比 AMO 和 AMP 柱分别高出约 10%和 13%。外排泵和抗生素失活是两种主要的抗性机制。NO3--N 沿补给方向逐渐减少（AMO、AMP 和 OXA 分别减少 26%、38%和 49%）。微生物共现网络表明，氮循环细菌是含水层群落中的关键种，氨化作用为氨氧化古菌（Ammonia-Oxidizing Archaea，AOA）的硝化过程提供 NH4+-N，促进 MAR 过程中的进一步反硝化脱氮。氮循环细菌是关键和活跃的 ARG 宿主，它们可以在抗生素胁迫下保持氮转化活性。总之，氮循环细菌在 MAR 过程中表现出亲密的协同作用和弹性抗性，以应对营养不良环境和β-内酰胺类抗生素的暴露。
