Ashwini M, Ray Mousumi, Sumana K, Halami Prakash M
Department of Microbiology, Faculty of Life Sciences, JSS Academy of Higher Education and Research, Mysuru, 570015 India.
Department of Microbiology and Fermentation Technology, CSIR- Central Food Technological Research Institute, Mysuru, 570020 India.
J Food Sci Technol. 2023 Feb;60(2):630-642. doi: 10.1007/s13197-022-05648-1. Epub 2022 Dec 6.
Lactic acid bacteria (LAB) being a reservoir of antibiotic resistance genes, tend to disseminate antibiotic resistance that possibly pose a threat to human and animal health. Therefore, the study focuses on the prevalence of macrolide-lincosamide-streptogramin- (MLS) resistance among LAB isolated from various food samples. Diverse phenotypic and genotypic MLS resistance were determined among the LAB species (n = 146) isolated from fermented food products (n = 6) and intestine of food-producing animals (n = 4). Double disc, triple disc diffusion and standard minimum inhibitory concentration (MIC) tests were evaluated for phenotypic MLS resistance. Specific primers for MLS resistance genes were used for the evaluation of genotypic MLS resistance and gene expressions using total RNA of each isolate at different antibiotic concentrations. The isolates identified are (n = 1) (n = 1) fermentum (n = 2) (n = 3) (n = 1) The MIC tests along with induction studies displayed cMLS, L phenotype, M phenotype, KH phenotype, I phenotype resistance among MLS antibiotics. Genotypic evaluation tests revealed the presence of B, A/E, A/B and C genes. Also, gene expression studies displayed increased level of gene expression to the twofold increased antibiotic concentrations. In the view of global health concern, this study identified that food samples and food-producing animals represent source of antibiotic resistant LAB that can disseminate resistance through food chain. This suggests the implementation of awareness in the use of antibiotics as growth promoters and judicious use of antibiotics in veterinary sectors in order to prevent the spread of antibiotic resistance.
乳酸菌（LAB）作为抗生素抗性基因的储存库，往往会传播抗生素抗性，这可能对人类和动物健康构成威胁。因此，本研究聚焦于从各种食品样本中分离出的乳酸菌对大环内酯 - 林可酰胺 - 链阳霉素（MLS）的抗性流行情况。在从发酵食品（n = 6）和产肉动物肠道（n = 4）中分离出的乳酸菌物种（n = 146）中，确定了不同的表型和基因型MLS抗性。对双纸片、三纸片扩散和标准最低抑菌浓度（MIC）试验进行了表型MLS抗性评估。使用MLS抗性基因的特异性引物，利用不同抗生素浓度下各分离株的总RNA评估基因型MLS抗性和基因表达。鉴定出的分离株有（n = 1）（n = 1）发酵乳杆菌（n = 2）（n = 3）（n = 1）。MIC试验以及诱导研究显示在MLS抗生素中存在cMLS、L表型、M表型、KH表型、I表型抗性。基因型评估试验揭示了B、A/E、A/B和C基因的存在。此外，基因表达研究显示，随着抗生素浓度增加两倍，基因表达水平也有所提高。鉴于全球健康问题，本研究确定食品样本和产肉动物是抗生素抗性乳酸菌的来源，这些乳酸菌可通过食物链传播抗性。这表明应提高对抗生素作为生长促进剂使用的认识，并在兽医领域合理使用抗生素，以防止抗生素抗性的传播。
