摘要
针对氯霉素难以生物降解的问题,本研究将纳米洋葱碳(carbon nano-onions,CNOs)作为导电材料投加到厌氧膜生物反应器(anaerobic membrane bioreactor,AnMBR)去除废水中的氯霉素(chloramphenicol,CAP),探讨了CAP的厌氧降解途径和抗生素抗性基因(ARG)分布的情况,解析了CNOs对氯霉素去除的强化作用。质谱检测结果表明CAP和参与三羧酸循环的物质之间发生了酯化反应,这些降解产物的毒性低于CAP。此外,CNOs的添加促进了部分三羧酸循环酶的上调,进一步降低了CAP的生物毒性。研究还发现CNOs可以增强ARG的水平基因转移,其中intI1基因的相对丰度显著增加。另一方面,AnMBR的膜组件有效截留了ARG。采用序批实验进一步研究CNOs对氯霉素去除的强化作用,结果表明,添加CNOs的实验组中,反应10 h时CAP去除率为90.4%,远高于未添加CNOs的对照组(59.4%)。此外,添加CNOs的厌氧生物体系24 h内甲烷产量为46.1 mL,远高于对照组,且产甲烷滞后时间更短。以上结果表明CNOs强化了厌氧生物体系对氯霉素废水的去除效果,降低了CAP的生物毒性,可为AnMBR处理抗生素废水提供参考。
To address the problem of difficult biodegradation of chloramphenicol(CAP),carbon nano-onions(CNOs)were used as a conductive material for the removal of CAP from wastewater by an anaerobic membrane bioreactor(AnMBR).The anaerobic degradation pathways of CAP and the distribution of antibiotic resistance genes(ARGs)were investigated,and the enhanced effect of CNOs on CAP removal was analyzed.Mass spectrometry data indicated that the esterification reactions occurred between CAP and substances involved in the tricarboxylic acid cycle,and these degradation products were less toxic than CAP.Moreover,the addition of CNOs promoted the up-regulation of some tricarboxylic acid cycle enzymes,which further reduced the biotoxicity of CAP.It was also found that CNOs enhanced horizontal gene transfer of ARGs,of which the relative abundance of intI1 gene significantly increased.On the other hand,the membrane module of AnMBR effectively sequestered ARGs.Sequential batch experiments were used to further investigate the enhanced effect of CNOs on CAP removal,and the results showed that the CAP removal rate in the experimental group with the addition of CNOs was 90.4%(10 h),which was much higher than that in the control group without CNOs(59.4%).Besides,the methane production of the anaerobic biological system with the addition of CNOs was 46.1 mL in 24 h,which was much higher than that of the control group,and the lag time for methane production was shorter.These results indicated that CNOs strengthened the removal effect of anaerobic biotic system on CAP wastewater and reduced the biotoxicity of CAP,which provided a certain theoretical basis for the treatment of antibiotic wastewater by AnMBR.
作者
朱明超
李娜
陆勇泽
胡朝霞
陈守文
ZHU Mingchao;LI Na;LU Yongze;HU Zhaoxia;CHEN Shouwen(School of Environmental and Biological Engineering,Nanjing University of Science and Technology,Nanjing 210094,China;College of Energy and Environment,Southeast University,Nanjing 211189,China;Tibet Key Laboratory of Water Pollution Control and Ecological Remediation of the State People's Committee of Tibet,Tibet University for Nationalities,Xianyang 712082,China;School of Information Engineering,Tibet University for Nationalities,Xianyang 712082,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2024年第5期1273-1282,共10页
Chinese Journal of Environmental Engineering
基金
国家重点研发计划资助项目(YFC 3203304)
国家自然科学基金资助项目(52170153、51708295)
西藏重点研发计划资助项目(XZ202301ZY0031G)
江苏省碳达峰与碳中和科技创新项目资助项目(BK2022003)。
关键词
纳米洋葱碳
厌氧膜生物反应器
氯霉素
抗生素抗性基因
废水处理
carbon nano onions
anaerobic membrane bioreactor
chloramphenicol
antibiotic resistance genes
wastewater treatment
