Kheadr E, Dabour N, Le Lay C, Lacroix C, Fliss I
Nutraceuticals and Functional Foods Institute (INAF), Université Laval, Québec, PQ, Canada, G1K 7P4.
Antimicrob Agents Chemother. 2007 Jan;51(1):169-74. doi: 10.1128/AAC.00261-06. Epub 2006 Oct 23.
The effects of acid, oxgall, and H(2)O(2) on susceptibilities to antibiotics and nisin were examined for 13 strains of bifidobacteria. Susceptibilities to ampicillin, cloxacillin, penicillin, vancomycin, kanamycin, neomycin, paramomycin, streptomycin, chloramphenicol, erythromycin, tetracycline, and nisin A were assayed by a microdilution broth method. Acid-, oxgall- and H(2)O(2)-stressed variants were produced and assayed. Exposure to a pH of 2.0 for 60 min reduced susceptibilities to cloxacillin and nisin A but increased susceptibilities to ampicillin, vancomycin, aminoglycosides, chloramphenicol, and erythromycin in a strain-dependent manner. Exposure to oxgall (0.3%) for 90 min increased susceptibilities to cell wall-directed antibiotics and aminoglycosides but increased resistances to tetracycline and nisin A. Oxidative stress increased the susceptibilities of 70% of the strains to ampicillin and chloramphenicol, of 50% of the strains to cloxacillin and tetracycline, and of 40% of the strains to erythromycin but did not affect susceptibilities to vancomycin, kanamycin, and nisin A. This study shows that exposure of bifidobacteria to stressful conditions resembling those in the gastrointestinal tract may substantially modify their susceptibilities to antibiotics and may thus affect their probiotic capacities, especially when they are used for the management of intestinal infections and antibiotic-associated diarrhea.
检测了酸、牛胆汁和过氧化氢对13株双歧杆菌抗生素敏感性和对乳链菌肽敏感性的影响。采用微量稀释肉汤法测定了双歧杆菌对氨苄西林、氯唑西林、青霉素、万古霉素、卡那霉素、新霉素、巴龙霉素、链霉素、氯霉素、红霉素、四环素和乳链菌肽A的敏感性。制备并检测了经酸、牛胆汁和过氧化氢应激处理的变异菌株。在pH 2.0条件下暴露60分钟会降低对氯唑西林和乳链菌肽A的敏感性，但会以菌株依赖性方式增加对氨苄西林、万古霉素、氨基糖苷类、氯霉素和红霉素的敏感性。在0.3%牛胆汁中暴露90分钟会增加对作用于细胞壁的抗生素和氨基糖苷类的敏感性，但会增加对四环素和乳链菌肽A的耐药性。氧化应激使70%的菌株对氨苄西林和氯霉素的敏感性增加，50%的菌株对氯唑西林和四环素的敏感性增加，40%的菌株对红霉素的敏感性增加，但不影响对万古霉素、卡那霉素和乳链菌肽A的敏感性。本研究表明，双歧杆菌暴露于类似于胃肠道中的应激条件下可能会显著改变其对抗生素的敏感性，从而可能影响其益生菌能力，尤其是在用于治疗肠道感染和抗生素相关性腹泻时。
