항암활성 및 Helicobacter pylori 억제능 유산균의 분리와 특성 규명

Abstract

To evaluate the inhibitory effect of kimchi lactic acid bacteria on H. pylori and AGS gastric cancer cell. The inhibitory effects of 31 strains among lactic acid bacteria(LAB) isolated from Kimch on H. pylori were tested and 4 strains of LAB have been selected as the strain which possesse the strong inhibitory effect against H. pylori KCCM 41756. Culture supernatants of 4 strains of LAB have a strong inhibitory activity on the urease activity of H. pylori KCCM 41756. The four selected strains were identified and named as Lactobacillus sakei WH1, Lactobacillus sakei SI3, Lactobacillus curvatus BU1, Lactobacillus plantarum NO1 based on biolog test and 16S rRNA sequences determination. Acid and bile tolerance of these four selected strains were investigated. The result of viability test in artificial gastric juice and bile the isolate showed high viability(108～109CFU/ml) in 0.05M sodium phosphate buffer(pH 3.0), artificial gastric juice and 0.3%, 0.5% oxgal solution. Hemolysis was used in 7% horse blood contain blood agar plate and streaking after incubated 48hr at 37℃, 5% CO₂. But hemolysis dosen't indicate a zone of clearing in the blood agar in the area surrounding a lactic acid bacteria colony. This study was also carried out to investigate the antimicrobial and anticancer activities of 4 strains of LAB. Four strains of LAB showed relatively wide range of antimicrobial activity against gram-positive bacteria including Bacillus subtilis ATCC 6633, Streptococcus faecalis ATCC 29212, Streptococcus mutans ATCC 25175, Micrococcus luteus ATCC 9341, Staphylococcus aureus ATCC 29213, Listeria monocytogenes ATCC 19113, Curtobacterium sp. Cf3 and gram-negative bacteria including Salmonella typhi ATCC 19430, Pseudomonas aeruginosa ATCC 27853, Escherichia coli O-157. Cytotoxicity of human foreskin normal cell BJ and inhibition ratio of human gastric cancer cell AGS in adding of the culture supernatants from the 4 strains of LAB were measured by MTT assay. The culture supernatants from the 4 strains of LAB exert the significant anticancer activity as well as the safety of normal cell. The isolated four LAB from kimchi should be applied to various foods, and be used as adjuncts in cancer therapy.