• Journal of Microbiology and Biotechnology
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• v.15 no.3
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• pp.603-608
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• 2005

We recently isolated a novel probiotic strain, Lactobacillus fermentum PL9005 (KCCM-10250), from infant feces and showed that it had a potential immunoenhancing effect. In the present study, a safety assessment of the bacteria was performed using a BALB/c mouse model. Mice were administered with L. fermentum PL9005 daily for 28 days. There were no detectable changes in body weight, feed intake, or clinical signs, and no significant difference in hematological parameters or blood biochemistry between the L. fermentum PL9005-fed and control groups. Bacterial translocation was detected in the mesenteric lymph nodes, liver, and spleen of some mice with and without L. fermentum PL9005 feeding, however, the organisms were not related to ingestion of L. fermentum PL9005; this was confirmed by PCR using a species-specific primer. No gross lesions were detected in the liver, spleen, or intestine of L. fermentum PL9005-fed or control mice. Mucosal thickness in the ileum, cecum, and colon of L. fermentum PL9005-fed mice was not significantly different from that of corresponding organs in control mice. No inflammation or epithelial cell degeneration in the intestines was observed in any mice. These results indicate that ingestion of L. fermentum PL9005 is safe in mice and can be applied in the functional food market.

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.167-170
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• 2004

Lactic acid bacteria (LABs) have been proposed as a potential oral allergy-therapeutic means of modulating immune phenotype expression in vivo, via promoting or reducing cytokine production. This study investigated the ability of LABs to suppress allergic response via modulating cytokine production in mice splenocytes. BALB/c mice were intraperitoneally primed with ovalbumin together with alum adjuvant to invoke antigen-specific Th1/Th2 cytokine-secreting cell populations in splenocytes. Spleen cells from mice fed with Lactobacillus confusus PL9001 (KCCM-10245), L. fermentum PL9005 (KCCM-10250), L. plantarum PL9011 (KCCM-10358), and Bifidobacterium infantis PL9506 (KCCM-10406) suppressed the levels of Th2 cell cytokines such as IL-4 and IL-5 during antigen sensitization. In addition, all mice fed with LABs induced secretion of Th1 cell cytokines such as IL-2 in splenocytes. These results suggested that LABs are anti-allergic agents, in view of their Th1/anti-Th2 immunoregulation.