Antibacterial activity of trichorabdal A from Rabdosia trichocarpa against Helicobacter pylori.

Rabdosia trichocarpa is used in a popular home-made remedy for gastric and stomachic complaints in Japan. A diterpene, trichorabdal A from R. trichocarpa, showed a very strong in vitro antibacterial activity against Helicobacter pylori. With regard to the antibacterial activity of the extract and constituents of R. trichocarpa against H. pylori, the effect of traditional use of this plant for the treatment of gastritis is probably due to the suppression of H. pylori since the extract of R. trichocarpa particularly inhibits the growth of H. pylori. It could be a promising native herb treatment for patients with gastric complaints including gastric ulcer caused by H. pylori.