尾菜中一株抗生素和铅交叉抗性乳酸菌的筛选及抗性特征  

Screening and resistance analysis of lactic acid bacteria cross-resistant to antibiotics and lead in vegetable waste

作　　者：黄熙瀛 张俊涛 邓丽莎 辜运富 HUANG Xiying;ZHANG Juntao;DENG Lisha;GU Yunfu(Department of Applied Microbiology,College of Resource Science and Technology,Sichuan Agricultural University,Chengdu 611130,China)

机构地区：[1]四川农业大学资源学院应用微生物学系,成都611130

出　　处：《应用与环境生物学报》2020年第2期319-324,共6页Chinese Journal of Applied and Environmental Biology

基　　金：教育部春晖项目(Z2016116);大学生创新训练项目(201710626034)资助

摘　　要：为探究尾菜表面附着的乳酸菌在重金属和抗生素协同选择下的抗性能力,以青菜尾菜为原料评价尾菜表面乳酸菌的环境安全性.通过纯培养方法对青菜尾菜中的乳酸菌进行分离,并对分离菌株进行庆大霉素、土霉素、环丙沙星、氯霉素、青霉素及磺胺间甲氧嘧啶和铅离子(Pb^(2+))的抗性能力测定.结果显示,从青菜尾菜中分离得到50株乳酸菌,有15株对上述供测抗生素均表现出抗性,10株对Pb^(2+)有抗性.其中菌株Lab99对Pb^(2+)的最低抑菌浓度(Minimum inhibitory concentration,MIC)值达到6 000 mg/L,对庆大霉素、青霉素和磺胺间甲氧嘧啶的MIC值均达到320 mg/L以上.另外,该菌株对Pb^(2+)和庆大霉素、磺胺间甲氧嘧啶、土霉素、氯霉素均具有交叉抗性.系统发育分析显示该菌在分类属于粪肠球菌(Enterococcus faecium).本研究表明青菜尾菜上具有对Pb^(2+)和抗生素有交叉抗性的乳酸菌菌株,结果可为重金属和抗生素交叉污染的环境修复治理提供科学依据.(图4表2参38)To explore the resistance ability of lactic acid bacteria(LAB)found in the leaf surface of waste vegetables under the synergistic selection of heavy metals and antibiotics,the environmental safety of LAB in the leaf surface of Brassica chinensis var.chinensis was evaluated.The pure culture method was used to isolate the culturable LAB strains in the waste vegetable leaves and then the resistance of the isolated LAB to antibiotics(e.g.,gentamicin,oxytetracycline,ciprofloxacin,chloramphenicol,penicillin,and sulfamonomethoxine)and heavy metals(e.g.,lead ion Pb2+)was evaluated.A total of 50 LAB strains were successfully isolated from the leaves of B.chinensis var chinensis.Among them,15 strains showed resistance to the six tested antibiotics and 10 strains were resistant to Pb2+.Lab99 showed a minimum inhibitory concentration(MIC)value of 6000 mg/L to Pb2+and the MIC values for gentamicin,penicillin,and sulfamonomethoxine were at least 320 mg/L.In addition,strain Lab99 showed a cross-resistance to Pb2+and gentamicin,sulfamonomethoxine,oxytetracycline,and chloramphenicol.Further phylogenetic analysis showed that the strain Lab99 was closely related to Enterococcus faecium.The LAB strains in the leaves of B.chinensis var.chinensis showed cross-resistance to Pb2+and antibiotics,which may provide scientific clues for remediating the cross-contamination of heavy metals and antibiotics in the environment.

关 键 词：尾菜 抗生素 重金属 乳酸菌 交叉抗性 

分 类 号：X17[环境科学与工程—环境科学]