Multifunctional effect of probiotic Lactococcus lactis KC24 isolated from kimchi

- Lactococcus lactis KC24 was characterized for its probiotic properties.
- L. lactis KC24 inhibited adhesion of Listeria. monocytogenes and Staphylococcus. aureus.
- Anti-inflammatory, antioxidant, and anticancer effect of L. lactis KC24 were verified.
- L. lactis KC24 may have potential as novel probiotics in functional foods.

The probiotic properties of Lactococcus lactis KC24 isolated from kimchi were studied. L. lactis KC24 retained activity in artificial gastric juice (pH 3.0, 0.1% pepsin for 2 h) and bile acid (0.1% oxgall for 24 h). This strain did not produce the carcinogenic enzyme, β-glucuronidase. L. lactis KC24 adhered strongly to Caco-2 cells (16.62% and 18.44% of cell adherence and high hydrophobicity, respectively). Antimicrobial effects of L. lactis KC24 were studied by the competition with other microorganisms to adhere to intestinal epithelial cells. L. lactis KC24 inhibited the adhesion of 6 pathogens (3 Listeria monocytogenes strains and 3 Staphylococcus aureus strains) to the mucus layer. The anti-inflammatory effect of L. lactis KC24 was demonstrated through the reduction of nitric oxide in the lipopolysaccharide-induced production. The antioxidant effect determined through ferric reducing antioxidant power (FRAP) and inhibition of β-carotene and linoleic acid oxidation was significant with a much higher FRAP value than that observed for ascorbic acid (1 mg/mL). The anticancer effect was observed against gastric carcinoma (AGS), colon carcinoma (HT-29 and LoVo), breast carcinoma (MCF-7), and lung carcinoma (SK-MES-1) cells (>50% cytotoxicity). These results indicate that L. lactis KC24 could potentially be used in the formulation of multifunctional probiotics products.