生态环境学报2024，Vol.33Issue(7)：1107-1116,10.DOI:10.16258/j.cnki.1674-5906.2024.07.012
强还原处理对土壤中常见抗生素及其抗性基因的影响研究
Effects of Reductive Soil Disinfestation on Common Antibiotics and Their Antibiotic Resistance Genes in Soil
摘要
Abstract
s:The enrichment of antibiotic-resistant pathogens and the spread of antibiotic resistance genes(ARGs)caused by the long-term accumulation of antibiotics in soil has become an environmental issue of great concern.To investigate the effect of reductive soil disinfestation(RSD)on antibiotics and associated ARGs,four antibiotics(tetracycline,oxytetracycline,sulfadiazine,and sulfamethoxazole)were selected,which are commonly used and are difficult to degrade,and a mixed antibiotic-contaminated soil was constructed.Each antibiotic was administered at a dose of 20 mg∙kg-1.Three treatments,CK(control without soil treatment),RCS(RSD incorporated with 2%corn straw),and RSR(RSD incorporated with 2%sugarcane bagasse),were performed and destructive sampling was conducted on days 7,14,and 28.High-performance liquid chromatography and fluorescence quantitative PCR were used to analyze the changes in antibiotic concentrations as well as the abundance of ARGs and mobile genetic elements(MGEs)during RSD treatment.The results showed that RSD treatment effectively degraded tetracyclines and sulfonamides in the soil.After 28 days of treatment,the degradation rate of sulfonamides was 45.2%-100%,which was better than that of tetracyclines,ranging from 33.5%to 57.2%.The RSR treatment had a better degradation effect on tetracycline and sulfadiazine than the RCS treatment,with degradation rates of up to 57.2%-64.8%,while the opposite was true for oxytetracycline,which was degraded up to 44.7%by the RCS treatment.The degradation of sulfamethoxazole by both RSD treatments was up to 100%after 14 days of treatment.The antibiotic concentration gradually decreased with the treatment time,and the two RSD treatments had different degradation effects on antibiotics.The absolute abundance of ARGs in the soil increased significantly after RSD treatment,and the effect of RCS treatment was stronger than that of the RSR treatment.With the extension of the treatment time,the relative abundance of ARGs such as tetM and qacH decreased in the RSD treatments,suggesting that the negative ecological effects of the increased ARGs were mitigated.The RSD treatment significantly reduced the relative abundance of IS26 in soil,suggesting that it can impair the horizontal transfer capacity of ARGs by ablating specific MGEs.Overall,RSD treatment can effectively degrade tetracyclines and sulfonamides in soil,and has the potential to reduce the abundance of ARGs and the risk of their spread.This study provides some theoretical and technical support for solving the problem of soil antibiotic contamination and reducing the risk of ARGs spread.关键词
强还原土壤处理/抗生素/抗生素抗性基因/可移动遗传元件/降解效应Key words
reductive soil disinfestation/antibiotics/antibiotic resistance genes/mobile genetic elements/degradation effects分类
资源环境引用本文复制引用
林于蓝,陈厚朴,于文豪,王宝英,张杨,张金波,蔡祖聪,赵军..强还原处理对土壤中常见抗生素及其抗性基因的影响研究[J].生态环境学报,2024,33(7):1107-1116,10.基金项目
国家自然科学基金项目(42090065 （）
42307385) （）
江苏省农业农村污染防治技术与装备工程研究中心开放资金项目(GCZXZD2301) （GCZXZD2301）
江苏省研究生科研与实践创新计划项目(KYCX22_1568 （）
KYCX23_1720) （）
南京师范大学学生科学基金项目(NSTW2022056) （NSTW2022056）
