Istituto di Microbiologia, Facoltà di Agraria, Università Cattolica del Sacro Cuore, Piacenza, Italy.
J Appl Microbiol. 2009 Nov;107(5):1559-68. doi: 10.1111/j.1365-2672.2009.04338.x. Epub 2009 Apr 27.
To assess the frequency of erythromycin- and tetracycline-resistant lactobacilli in Italian fermented dry sausages.
We isolated lactobacilli colonies from 20 salami from the north of Italy (Piacenza province) using selective medium supplemented with erythromycin or tetracycline; we determined the minimum inhibitory concentration and searched for selected erythromycin and tetracycline resistance genes. A total of 312 lactobacilli colonies were genetically ascribed to 60 different strains belonging to seven Lactobacillus species. Lactobacillus sakei, Lactobacillus curvatus and Lactobacillus plantarum were the most frequently found species. Thirty strains (50%) were phenotypically resistant to erythromycin, 45 (75%) to tetracycline and 27 (45%) were resistant to both. The most frequently detected resistance genes were tet(M) and erm(B).
This study provides evidence of the presence of tetracycline- and, to a lesser extent, erythromycin-resistant lactobacilli in fermented dry sausages produced in northern Italy.
Although these antibiotic-resistant lactobacilli could serve as reservoir organisms, in our study, 16 of 20 salami could be considered safe in regard to possible antibiotic resistance gene transfer to pathogens, whereas 4 of 20 could represent a borderline situation.
评估意大利发酵干香肠中红霉素和四环素耐药乳杆菌的频率。
我们使用添加红霉素或四环素的选择性培养基从意大利北部（皮亚琴扎省）的 20 个萨拉米香肠中分离出乳杆菌菌落；我们确定了最低抑菌浓度，并寻找了选定的红霉素和四环素耐药基因。共分离出 312 个乳杆菌菌落，分为 60 株，属于 7 个乳杆菌种。乳杆菌属、弯曲乳杆菌和植物乳杆菌是最常发现的种。30 株（50%）表现出对红霉素的表型耐药，45 株（75%）对四环素耐药，27 株（45%）对两者均耐药。最常检测到的耐药基因是 tet（M）和 erm（B）。
本研究证明了在意大利北部生产的发酵干香肠中存在四环素和（在较小程度上）红霉素耐药乳杆菌。
尽管这些抗生素耐药乳杆菌可能是储库生物，但在我们的研究中，20 个萨拉米香肠中有 16 个可被认为在抗生素耐药基因转移到病原体方面是安全的，而 20 个中有 4 个是边缘情况。
