Anti-Helicobacter pylori activity of Chinese tea: in vitro study.
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.
Yee
Y K
YK
Department of Medicine, Tuen Mun Hospital, Hong Kong; Department of Pharmacology, Faculty of Medicine, University of Hong Kong, Hong Kong. ykyee@bigfoot.com
Koo
M W
MW
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
D000900:Anti-Bacterial Agents; D004791:Enzyme Inhibitors; D005419:Flavonoids; D013662:Tea; D008795:Metronidazole; D002392:Catechin; C057580:gallocatechol