title: Anti-Helicobacter pylori activity of Chinese tea: in vitro study.
abstract: BACKGROUND
  Chinese tea has an antibacterial activity against a wide range of bacteria. However, its activity against Helicobacter pylori has not been reported.
  
  
  METHODS
  In this study the anti-Helicobacter pylori effects of a Chinese tea (Lung Chen tea), and two tea catechins, epigallocatechin gallate and epicatechin and their minimum inhibitory concentrations (MICs) were examined. The effect of Lung Chen on metronidazole resistance was also studied using the E-test.
  
  
  RESULTS
  Lung Chen, epigallocatechin gallate and epicatechin all inhibited the growth of H. pylori. The MIC90 for Lung Chen was 0. 25-0.5% (w/w) and that of epigallocatechin gallate and epicatechin were 50-100 and 800-1600 microg/mL, respectively. Epigallocatechin gallate is probably the active ingredient responsible for most of the anti-H. pylori activity of Chinese tea. Lung Chen did not reverse metronidazole resistance.
  
  
  CONCLUSIONS
  Chinese tea has anti-H. pylori activity in a daily consumed concentration, and epigallocatechin gallate is probably the active ingredient responsible for the action.
authors.affiliation: Department of Medicine, Tuen Mun Hospital, Hong Kong; Department of Pharmacology, Faculty of Medicine, University of Hong Kong, Hong Kong. ykyee@bigfoot.com
authors.forename: Y K
authors.initials: YK
authors.lastname: Yee
authors.forename: M W
authors.initials: MW
authors.lastname: Koo
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002392:Catechin / Q000031:analogs & derivatives*; D004305:Dose-Response Relationship, Drug; D004351:Drug Resistance; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005419:Flavonoids / Q000494:pharmacology*; D016480:Helicobacter pylori / Q000187:drug effects*; D006801:Humans; D066298:In Vitro Techniques; D008795:Metronidazole / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D013662:Tea
chemical_list: D000900:Anti-Bacterial Agents; D004791:Enzyme Inhibitors; D005419:Flavonoids; D013662:Tea; D008795:Metronidazole; D002392:Catechin; C057580:gallocatechol