グリチルレチン酸誘導体であるサクシニルグリチルレチン酸ニナトリウムのStreptococcus mutansに対する抗菌効果について

• Material Type: 博士論文
• Title: グリチルレチン酸誘導体であるサクシニルグリチルレチン酸ニナトリウムのStreptococcus mutansに対する抗菌効果について
• Author/Editor: 山下, 剛史
• Author Heading: 山下, 剛史 ヤマシタ, タカヒト
• Publication, Distribution, etc.: The Societies and John Wiley & Sons Australia, Ltd
• Alternative Title: Antibacterial activity of disodium succinoyl glycyrrhetinate, a derivative of glycyrrhetinic acid against Streptococcus mutans
• Degree grantor/type: 鹿児島大学
• Date Granted: 2020-01-28
• Dissertation Number: 甲総研第532号
• Degree Type: 博士(歯学); Doctor of Philosophy in Dental Science
• Text Language Code: eng
• Subject Heading: Antibacterial agent; Streptococcus mutans
• Target Audience: 一般
• Note (General): 博士論文全文, 博士論文要旨, 最終試験結果の要旨, 論文審査の要旨; Streptococcus mutans is a cariogenic bacterium that localizes in the oral cavity. Glycyrrhetinic acid (GRA) is a major component of licorice extract. GRA and several derivatives, including disodium succinoyl glycyrrhetinate (GR-SU), are known to have anti-inflammatory effects in humans. In this study, the antimicrobial effect of GRA and its derivatives against the S. mutans UA159 strain were investigated. Minimum inhibitory concentrations (MICs) of GRA and GR-SU showed antibacterial activity against the S. mutans strain, whereas other tested derivatives did not. Because GR-SU is more soluble than GRA, GR-SU was used for further experiments. The antibacterial activity of GR-SU against 100 S. mutans strains was evaluated and it was found that all strains are susceptible to GR-SU, with MIC values below 256 µg/mL. A cell viability assay showed that GR-SU has a bacteriostatic effect on S. mutans cells. As to growth kinetics, sub-MICs of GR-SU inhibited growth. The effect of GR-SU on S. mutans virulence was then investigated. GR-SU at sub-MICs suppresses biofilm formation. Additionally, GR-SU greatly suppresses the pH drop caused by the addition of glucose and glucose-induced expression of the genes responsible for acid production (ldh and pykF) and tolerance (aguD and atpD). Additionally, expression of enolase, which is responsible for the carbohydrate phosphotransferase system, was not increased in the presence of GR-SU, indicating that GR-SU suppresses incorporation of sugars into S. mutans. In conclusion, GR-SU has antibacterial activity against S. mutans and also decreases S. mutans virulence. This is the peer reviewed version of the following article: Takahito Yamashita, Miki Kawada-Matsuo, Tamaki Katsumata, Atsuko Watanabe, Yuichi Oogai, Yoshihiro Nishitani, Shouichi Miyawaki, Hitoshi Komatsuzawa. Safety, speed, and effectiveness of air transportation for neonates Microbiology and immunology (2019), 63(7), 251-260 © 2019 The Societies and John Wiley & Sons Australia, Ltd which has been published in final form at https://doi.org/10.1111/1348-0421.12717 This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.
• Format (IMT): application/pdf
• Source: Diss_山下_剛史_ISK532_2019 （fulltext）; https://ir.kagoshima-u.ac.jp/record/14993/files/Diss_%E5%B1%B1%E4%B8%8B_%E5%89%9B%E5%8F%B2_ISK532_2019.pdf
• Access Restrictions: インターネット公開
• Data Provider (Database): 国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）; https://irdb.nii.ac.jp
• Original Data Provider (Database): 鹿児島大学 : 鹿児島大学リポジトリ