title: Antibacterial activity of polyphenol components in oolong tea extract against Streptococcus mutans.
abstract: The purpose of the present study was to determine the antibacterial activity of oolong tea extract on oral streptococci, including Streptococcus mutans and Streptococcus sobrinus, and to identify the response to its components. Antibacterial activity was found when the extract was added to S. mutans cells in chemically defined medium but not in complex broth media. Further, pretreatment with bovine serum albumin reduced the antibacterial activity. The extract showed antibacterial activity against all of the oral streptococci examined, with the highest activity against S. mutans MT8148R. This activity was found to originate from a monomeric polyphenol-rich fraction, and it was stronger than that of pure polyphenols. Moreover, some combinations of monomeric polyphenols showed the highest level of antibacterial activity. These results suggest that the antibacterial activity of oolong tea extract is caused by a synergistic effect of monomeric polyphenols, which can easily bind to proteins.
authors.affiliation: Department of Pediatric Dentistry, Osaka University Graduate School of Dentistry, Osaka, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Sasaki
authors.forename: M
authors.initials: M
authors.lastname: Matsumoto
authors.forename: T
authors.initials: T
authors.lastname: Tanaka
authors.forename: M
authors.initials: M
authors.lastname: Maeda
authors.forename: M
authors.initials: M
authors.lastname: Nakai
authors.forename: S
authors.initials: S
authors.lastname: Hamada
authors.forename: T
authors.initials: T
authors.lastname: Ooshima
mesh_terms: D000818:Animals; D002392:Catechin / Q000494:pharmacology*; D002417:Cattle; D015169:Colony Count, Microbial; D004357:Drug Synergism; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D013291:Streptococcus / Q000187:drug effects; D013295:Streptococcus mutans / Q000187:drug effects*; D013662:Tea / Q000737:chemistry
chemical_list: D010936:Plant Extracts; D013662:Tea; D012710:Serum Albumin, Bovine; D002392:Catechin