Carasi Paula, Díaz Mariángeles, Racedo Silvia M, De Antoni Graciela, Urdaci María C, Serradell María de los Angeles
Cátedra de Microbiología, Departamento de Ciencias Biológicas, de La Plata, 47 y 115 s/n, CP, 1900 La Plata, Argentina.
Laboratoire de Microbiologie et Biochimie Appliquée (LBMA), Université de Bordeaux, UMR 5248, Bordeaux Sciences Agro, 1 Cours du Général de Gaulle, 33175 Gradignan, France.
Biomed Res Int. 2014;2014:208974. doi: 10.1155/2014/208974. Epub 2014 May 13.
Lactobacilli are generally regarded as safe; however, certain strains have been associated with cases of infection. Our workgroup has already assessed many functional properties of Lactobacillus kefiri, but parameters regarding safety must be studied before calling them probiotics. In this work, safety aspects and antimicrobial activity of L. kefiri strains were studied. None of the L. kefiri strains tested caused α- or β-hemolysis. All the strains were susceptible to tetracycline, clindamycin, streptomycin, ampicillin, erythromycin, kanamycin, and gentamicin; meanwhile, two strains were resistant to chloramphenicol. On the other hand, all L. kefiri strains were able to inhibit both Gram(+) and Gram(-) pathogens. Regarding the in vitro results, L. kefiri CIDCA 8348 was selected to perform in vivo studies. Mice treated daily with an oral dose of 10(8) CFU during 21 days showed no signs of pain, lethargy, dehydration, or diarrhea, and the histological studies were consistent with those findings. Moreover, no differences in proinflammatory cytokines secretion were observed between treated and control mice. No translocation of microorganisms to blood, spleen, or liver was observed. Regarding these findings, L. kefiri CIDCA 8348 is a microorganism isolated from a dairy product with a great potential as probiotic for human or animal use.
乳酸杆菌通常被认为是安全的；然而，某些菌株与感染病例有关。我们的工作组已经评估了开菲尔乳杆菌的许多功能特性，但在将它们称为益生菌之前，必须研究其安全性参数。在这项工作中，研究了开菲尔乳杆菌菌株的安全性和抗菌活性。所测试的开菲尔乳杆菌菌株均未引起α-或β-溶血。所有菌株对四环素、克林霉素、链霉素、氨苄青霉素、红霉素、卡那霉素和庆大霉素敏感；同时，有两个菌株对氯霉素耐药。另一方面，所有开菲尔乳杆菌菌株都能够抑制革兰氏阳性和革兰氏阴性病原体。基于体外实验结果，选择开菲尔乳杆菌CIDCA 8348进行体内研究。在21天内每天口服10⁸CFU剂量的小鼠未表现出疼痛、嗜睡、脱水或腹泻的迹象，组织学研究结果与这些发现一致。此外，在治疗组和对照组小鼠之间未观察到促炎细胞因子分泌的差异。未观察到微生物向血液、脾脏或肝脏的转移。基于这些发现，开菲尔乳杆菌CIDCA 8348是一种从乳制品中分离出的微生物，具有作为人类或动物益生菌的巨大潜力。
