Probiotic and Antioxidant Properties of Novel KCCM 12203P Isolated from Kimchi and Evaluation of Immune-Stimulating Activities of Its Heat-Killed Cells in RAW 264.7 Cells.

The purpose of this study was to determine the probiotic properties of KCCM 12203P isolated from the Korean traditional food kimchi and to evaluate the antioxidative activity and immune-stimulating potential of its heat-killed cells to improve their bio-functional activities. GG, which is a representative commercial probiotic, was used as a comparative sample. Regarding probiotic properties, KCCM 12203P was resistant to 0.3% pepsin with a pH of 2.5 for 3 h and 0.3% oxgall solution for 24 h, having approximately a 99% survival rate. It also showed strong adhesion activity (6.84%) onto HT-29 cells and did not produce β-glucuronidase but produced high quantities of leucine arylamidase, valine arylamidase, β-galactosidase, and -acetyl-β- glucosaminidase. For antioxidant activity, it appeared that viable cells had higher radical scavenging activity in the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay, while in the 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assay, heat-killed cells had higher antioxidant activity. Additionally, KCCM 12203P showed higher lipid oxidation inhibition ability than GG; however, there was no significant difference ( < 0.05) between heat-killed cells and control cells. Furthermore, heat-killed KCCM 12203P activated RAW 264.7 macrophage cells without cytotoxicity at a concentration lower than 10 CFU/ml and promoted higher gene expression levels of inducible nitric oxide synthase, interleukin-1β, and interleukin-6 than GG. These results suggest that novel KCCM 12203P could be used as a probiotic or applied to functional food processing and pharmaceutical fields for immunocompromised people.