Probiotics are dietary supplements containing viable, non-pathogenic microorganisms that interact with the gastrointestinal microflora and directly with the immune system. The possible health effects of probiotics include modulating the immune system and exerting antibacterial, anticancer, and anti-mutagenic effects. The purpose of this study was to isolate, identify, and characterize novel strains of probiotics from the faeces of Korean infants. Various assays were conducted to determine the physiological features of candidate probiotic isolates, including Gram staining, 16S rRNA gene sequencing, tolerance assays to stimulated gastric juice and bile salts, adherence ability assays, antibiotic susceptibility testing, and assays of immunomodulatory effects. Based on these morphological and biochemical characteristics, five potential probiotic isolates (Enterococcus faecalis BioE EF71, Lactobacillus fermentum BioE LF11, Lactobacillus plantarum BioE LPL59, Lactobacillus paracasei BioE LP08, and Streptococcus thermophilus BioE ST107) were selected. E. faecalis BioE EF71 and L. plantarum BioE LPL59 showed high tolerance to stimulated gastric juice and bile salts, and S. thermophilus BioE ST107 as well as these two strains exhibited stronger adherence ability than reference strain Lactobacillus rhamnosus GG. All five strains inhibited secretion of lipopolysaccharide-induced pro-inflammatory cytokines IL-6 and TNF-α in RAW264.7 macrophages in vitro. L. fermentum BioE LF11, L. plantarum BioE LPL59, and S. thermophilus BioE ST107 enhanced the production of anti-inflammatory cytokine IL-10. Overall, our findings demonstrate that the five novel strains have potential as safe probiotics and encouraged varying degrees of immunomodulatory effects.

High-protein fermented whey beverage (FWB) was manufactured using whey protein concentrate (WPC) and Lactobacillus plantarum DK211 isolated from kimchi. This study was designed to evaluate the anti-obesity activity of FWB in male rats fed a high-fat diet. Male Sprague-Dawley rats were randomly assigned to three groups (n=8 per group). The three groups differed in their diet; one group received a normal diet (ND), another, a high-fat diet (HD), and the third, a HD plus fermented whey beverage (HDFWB), for 4 wk. Supplementation with FWB (the HDFWB group) prevented weight gain and body fat accumulation. The food intake in the HDWFB group was significantly lower (p<0.05) than that of the HD group. The HDWFB group also showed a significant decrease in organ weights (p<0.05), except for the weight of the testis. There was a significant decrease in total cholesterol, LDL-cholesterol, and triglycerides in the HDFWB group compared with the HD group (p<0.05), but there was no significant difference in serum HDL-cholesterol levels among the experimental groups. Rats ingesting FWB (the HDFWB group) also showed a significant decrease in blood glucose levels, and plasma levels of insulin, leptin, and ghrelin compared to HD group (p<0.05). These results indicate that FWB has beneficial effects on dietary control, weight control, and reduction in fat composition and serum lipid level; consequently, it may provide antiobesity and hypolipidemic activity against high fat diet-induced obesity in rats.