碳量子点调控希瓦氏菌还原二硝基联苯的机制  

The mechanism of carbon quantum dots to regulate the reduction of 2,2’-dinitrobiphenyl by Shewanella

作　　者：王贺飞[1,2] 沈可 张文康 宋瑶 任冲飞 杨晨 高彦征 WANG He-fei;SHEN Ke;ZHANG Wen-kang;SONG Yao;REN Chong-fei;YANG Chen;GAO Yan-zheng(Key Laboratory of Groundwater Resources and Environment,Ministry of Education,Jilin University,Changchun 130021,China;College of Resources and Environmental Sciences,Nanjing Agricultural University,Nanjing 210095,China)

机构地区：[1]吉林大学,地下水资源与环境教育部重点实验室,吉林长春130021 [2]南京农业大学资源与环境科学学院,江苏南京210095

出　　处：《中国环境科学》2024年第11期6418-6425,共8页China Environmental Science

基　　金：地下水资源与环境教育部重点实验室开放课题项目(202207005KF);国家自然科学基金项目(42207025);江苏省基础研究计划项目(BK20221025)。

摘　　要：土壤中广泛存在的希瓦氏菌(Shewanella)可通过胞外途径还原多种污染物.针对决定胞外还原效率的电子传递关键环节,以奥奈达希瓦氏菌(S.oneidensisMR-1)为模式微生物,研究了生物炭经硝酸氧化释放的碳量子点(CQDs)对该过程的强化规律和机制.发现制备的CQDs呈类球形,粒径为1.5~4nm,表面富含活性含氧官能团.Mtr通路是希瓦氏菌MR-1还原2,2’-二硝基联苯的主要电子传递通路,SirCD蛋白也参与了还原过程;CQDs可促进希瓦氏菌MR-1还原污染物的电子传递,降低污染物对菌体的毒性效应,提高2,2’-二硝基联苯的还原效率.土壤中的针铁矿阻碍希瓦氏菌MR-1还原2,2’-二硝基联苯,CQDs对此有一定缓解;腐殖酸可促进CQDs调控希瓦氏菌MR-1还原2,2’-二硝基联苯的反应.Shewanella,which is widely presented in soil,can reductively transform a variety of pollutants through extracellular electron transport pathways.Carbon quantum dots(CQDs)were produced from biochar through oxidation by nitric acid,and the the effectiveness and mechanism of CQDs to regulate the reduction of 2,2’-dinitrobiphenyl by the model microorganism(S.oneidensis MR-1)were studied.The produced CQDs were spherical with a particle size of 1.5~4nm,and the surface was rich in oxygen-containing functional groups,which were active for electron transfer.Mtr pathway was the main electron transport pathway for the reduction of 2,2’-dinitrobiphenyl by S.oneidensis MR-1,and SirCD was also involved in the reduction.CQDs can promote the electron transport in the reduction of 2,2’-dinitrobiphenyl by S.oneidensis MR-1,decrease the toxic effect of the pollutants on bacteria,thus improving the reduction efficiency.Goethite prevented reduction of 2,2’-dinitrobiphenyl by S.oneidensis MR-1,which can be alleviated by CQDs.Humic acid and CQDs promoted the reduction of 2,2’-dinitrobiphenyl by S.oneidensis MR-1.

关 键 词：碳量子点 2 2’-二硝基联苯 奥奈达希瓦氏菌 影响因素 

分 类 号：X53[环境科学与工程—环境工程]