有机白萝卜表皮附生乳酸菌抗生素耐药性分析

Antibiotic Resistance of Epibiotic Lactic Acid Bacteria on the Surface of Organic White Radish

以市售有机白萝卜为研究对象,分析其表皮附生乳酸菌对四环素(tetracycline,TET)、链霉素(streptomycin,STR)和青霉素G(penicillin G,PEN)的耐药性。分离菌株的生理生化特征、随机扩增多态性DNA聚类(random amplified polymorphic DNA,RAPD)、16S r RNA、耐药性和耐药表型多态分析表明:有机白萝卜表皮附生有约4.67×103 CFU/cm2的乳酸菌。分离的187株乳酸菌分别属于Pediococcus pentosaceus(114/187)、Weissella cibaria(9/187)、Leuconostoc mesenteroides(18/187)、Leuconostoc pseudomesenteroides(7/187)、Leuconostoc citreum(20/187)和Leuconostoc holzapfelii(19/187)。其中,25株(13.37%)对TET、STR和PEN表现出单一或多重耐药性。在P.pentosaceus中,分别有2株对STR、TET和PEN三重耐药,13株对STR和TET二重耐药和4株对TET单一耐药;L.citreum中,分别有1株对STR、TET和PEN三重耐药和1株对STR单一耐药;L.mesenteroides中,分别有1株对TET单一耐药和1株对TET和PEN二重耐药;L.pseudomesenteroides和W.cibaria中,分别有1株对STR和TET、STR和PEN二重耐药。

The epibiotic lactic acid bacteria(LAB) on the surface of organic radish were investigated by MRS culture,physiological and biochemical characteristics,RAPD,16 S r RNA,antibiotic resistance and phenotype polymorphism.Approximately 4.67 × 103 CFU/cm2 LAB including 187 isolates colonized on the surface of organic white radish.These isolates were assigned to Pediococcus pentosaceus(114/187),Weissella cibaria(9/187),Leuconostoc mesenteroides(18/187),Leuconostoc pseudomesenteroides(7/187),Leuconostoc citreum(20/187) and Leuconostoc holzapfelii(19/187),respectively.And 25(13.37%) isolates displayed single-drug or multi-drug resistance to tetracycline(TET),streptomycin(STR) and penicillin G(PEN).Of these P.pentosaceus isolates,2 had triplicate resistance to STR,TET and PEN,13 had double resistance to TET and STR,and 4 had single resistance to STR.Of these L.citreum isolates,1 had triplicate resistance to STR,TET and PEN,and 1 had the solo resistance to STR.Furthermore,2 L.mesenteroides isolates with TET resistance and double resistance TET and PEN respectively were found,and on the surface of white radish there were 1 L.pseudomesenteroides strain and 1 W.cibaria strain showing double resistance to STR and TET and double resistance to STR and PEN,respectively.