title: Kuwanon G: an antibacterial agent from the root bark of Morus alba against oral pathogens.
abstract: Kuwanon G was isolated from the ethyl acetate fraction of methanol extract of Morus alba and its structure was elucidated by 13C-NMR, 1H-NMR and FAB-MS. Antibacterial activity of kuwanon G was investigated by the minimum inhibitory concentration (MIC) test and the viable cell count method. MIC of kuwanon G against Streptococcus mutans causing dental caries was determined to be 8.0 microg/ml. The bactericidal test showed that kuwanon G completely inactivated S. mutans at the concentration 20 microg/ml in 1 min. Kuwanon G also significantly inhibited the growth of other cariogenic bacteria such as Streptococcus sobrinus and Streptococcus sanguis, and Porpyromonas gingivalis causing periodontitis. Transmission electron microscopy (TEM) of kuwanon G treated cells demonstrated remarkable morphological damage of the cell wall and condensation of the cytoplasm.
authors.affiliation: Department of Biotechnology and Bioproducts Research Center, Yonsei University, Seoul 120-749, South Korea.
authors.forename: K M
authors.initials: KM
authors.lastname: Park
authors.forename: J S
authors.initials: JS
authors.lastname: You
authors.forename: H Y
authors.initials: HY
authors.lastname: Lee
authors.forename: N I
authors.initials: NI
authors.lastname: Baek
authors.forename: J K
authors.initials: JK
authors.lastname: Hwang
mesh_terms: D000900:Anti-Bacterial Agents / Q000302:isolation & purification / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000648:ultrastructure; D015169:Colony Count, Microbial; D005419:Flavonoids / Q000302:isolation & purification / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D008854:Microscopy, Electron; D031625:Morus / Q000737:chemistry*; D024301:Plant Bark / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry; D012997:Solvents
chemical_list: D000900:Anti-Bacterial Agents; D005419:Flavonoids; D012997:Solvents; C095194:kuwanon G