Antibiotic Resistance of Lactobacillus sp. Isolated from Commercial Probiotic Preparations

Abstract

The aim of our study was to assess the antibiotic resistance among commercially available probiotic Lactobacilli. A total of 30 isolates were characterized after isolation from 19 commercial products, including Lactobacillus rhamnosus, Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus reuteri, Lactobacillus plantarum and Lactobacillus fermentum. All the isolates were further subjected to antibiotic susceptibility test using disc diffusion method against a total of 45 antibiotics. Most of the isolates were found to exhibit multiple resistance against some of the most commonly used antibiotics. The isolates showed high level of resistance toward nalidixic acid, vancomycin, kanamycin, teicoplanin, co-trimoxazole, amikacin, streptomycin, norfloxacin, cefepime and nitrofurantoin. Besides, isolates displayed a low level of resistance toward tobramycin, gentamicin, ampicillin, cefaclor, methicillin, penicillin, tetracycline, levofloxacin, azithromycin, chloramphenicol, amoxyclav, sulbactam, oxacillin, ofloxacin, ciprofloxacin, cloxacillin and novobiocin. All the isolates were found to be susceptible against cefatrixone, ceftazidime, cefadroxil, cefotaxime, cephalothin, cefoperazone and netillin, whereas none of the strains showed resistant to clindamycin, erythromycin, linezolid, quinupristin/dalfopristin and doxycycline. The present study showed that antibiotic resistance is prevalent in different species of probiotic strains, which may pose a food safety concern. Hence, antibiotic sensitivity should be considered as an important part of safety assessment for the evaluation of probiotics.

Antibiotic Susceptibility of Lactobacillus sp. Isolated from Commercial Probiotic Products by E-Test Strip Method

“…Many of them were found to exhibit multiple resistance against commonly used antibiotics. Out of 30 tested isolates, 29 were found to have resistance against a wide array of antibiotics (Sharma et al, 2015). The MIC of 29 probiotic isolates which showed resistance in disc diffusion assay was further tested to determine their MIC values against 30 antibiotics by E-test strip method.…”

Organic whey as a source of Lactobacillus strains with selected technological and antimicrobial properties

“…Additionally, food chain might be considered one of the main routes of antibiotic resistance transmission from bacteria to humans. In the recent years, there has been an increase in the number of scientific reports, mentioning LAB as the potential reservoirs of antibiotic resistance (Agaliya & Jeevaratnam, 2012), including probiotic bacteria (Jose et al, 2015;Wong et al, 2015;Sharma et al, 2016). Susceptibility or resistance and presence of the resistance genes of the tested Lactobacillus strains are shown in Table 6.…”

“…When bacteria strains demonstrate resistance by phenotypic methods, it is reasonable to apply genetic methods (Sharma et al, 2016). In the genetic study, some strains do not match any of the studied resistance genes.…”

Determination of antibiotic resistance of lactic acid bacteria isolates of probiotic foods

“…Sharma ve diğ. [2] 19 adet ticari propiyotik ürünlerden elde ettikleri 7 adet L. acidophilus izolatlarının yüksek dizeyde nalidiksik asit, siprofloksasin ve levoflaksasin direnci gösterdiğini bulmuştur. Nitekim çalışmamızda L. acidophilus izolatlarında da yüksek düzeyde siprofloksasin direnci saptanmış ve literatürdeki sonuçları desteklemiştir.…”

“…Antibiyotik direncine neden olan önemli faktörlerden bir diğeri ise plazmitlerin gıda ve insan kaynaklı mikrobiyal flora ile patojenler arasında transfer edilebilmesidir. Bu da gıdalarda antibiyotik dirençli mikroorganizmaların artan bir risk olduğunu ve antibiyotik direncinin insanlarda artmasındaki temel kaynaklardan biri olduğunu ortaya çıkarmıştır [2].…”