Interference of in vitro and in vivo growth of several intestinal bacteria by Lactococcus strains

• Published in: Journal of microbiology and biotechnology Vol. 18; no. 7; pp. 1286 - 1289
• Main Authors: Kimoto-Nira, Hiromi (National Institute of Livestock and Grassland Science, Ibaraki, Japan), E-mail: anne@affrc.go.jp, Ohmomo, Sadahiro (National Institute of Livestock and Grassland Science, Ibaraki, Japan), Nomura, Masaru (National Institute of Livestock and Grassland Science, Ibaraki, Japan), Kobayashi, Miho (National Institute of Livestock and Grassland Science, Ibaraki, Japan), Mizumahi, Koko (National Institute of Livestock and Grassland Science, Ibaraki, Japan), Okamoto, Takashi (National Agricultural Research Center for Hokkaido Region, Hokkaido, Japan)
• Format: Journal Article
• Language: English
• Published: Seoul Korean Society for Applied Microbiology 01.07.2008; 한국미생물·생명공학회
• Subjects: Animals; Antibiosis; Bacteria - growth & development; Biological and medical sciences; Biotechnology; CRECIMIENTO; CROISSANCE; Escherichia coli - growth & development; Female; Fundamental and applied biological sciences. Psychology; GROWTH; INHIBICION; INHIBITION; intestinal microflora; Intestines - microbiology; lactococci; Lactococcus - physiology; Mice; Mice, Inbred BALB C; Microbial Viability; PROBIOTICOS; PROBIOTICS; Probiotics - chemistry; PROBIOTIQUE; 생물학; Probiotic; Lactic acid bacteria; Growth; Interference; Gut; Microflora; growth inhibition; In vitro; Streptococcaceae; In vivo; Probiotics; Lactococcus; lactococci; Bacteria; Micrococcales; intestinal microflora; Inhibition
• ISSN: 1017-7825

The ability of Lactococcus strains to inhibit the growth of intestinal bacteria was examined. In in vitro cocultures, we observed that among eighteen Lactococcus strains tested, the ability to inhibit growth of Escherichia coli varied, with the L. lactis N7 showing the greatest growth inhibition. Strain N7 (8.94×10∨10 CFU/day for 7 days) was orally administered to mice, and the viable count of strain N7 in feces appeared at a level of 10∨4-5 CFU/g. After administration, the proportion of Bacteroidaceae to total intestinal bacteria decreased. Lactococci may act as probiotic bacteria by inhibiting the growth of harmful bacteria.