Planta Med 1998; 64(4): 324-327
DOI: 10.1055/s-2006-957443
Papers
Pharmacology
© Georg Thieme Verlag Stuttgart · New York

Proanthocyanidins from the Bark of Hamamelis virginiana Exhibit Antimutagenic Properties against Nitroaromatic Compounds

Andreas Dauer1 , Petra Metzner2 , Oskar Schimmer2
  • 1Salus-Haus, Naturarzneimittel, Bruckmühl, Germany
  • 2Institut für Botanik und Pharmazeutische Biologie, Friedrich-Alexander-Universität Erlangen-Nümberg, Erlangen, Germany
Weitere Informationen

Publikationsverlauf

1997

1998

Publikationsdatum:
04. Januar 2007 (online)

Abstract

The antimutagenic activity of Hamamelis virginiana bark was examined in the Ames assay. A commercial tincture and a methanolic extract showed dose-dependent inhibitory effects on mutagenicity induced by 2-nitrofluorene. Tannin-free samples did not display any inhibition. Bioassay-guided fractionation resulted in the isolation of two active fractions which were shown to contain oligomeric proanthocyanidins. They were capable of inhibiting the mutagenicity of selected nitroaromatic compounds. The mechanism of antimutagenic action was also studied. The proanthocyanidins did not act as bioantimutagens, but rather as direct-acting desmutagens. The antimutagenic effect increased with an increasing degree of polymerisation in the proanthocyanidins. The most active fraction consisted of catechin and gallocatechin oligomers with an average polymerisation degree of 9.2.