Safety assessment of Lactobacillus fermentum PL9005, a potential probiotic lactic acid bacterium, in mice

Abstract

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.