Planta Medica, Table of Contents Planta Med 1997; 63(2): 111-114DOI: 10.1055/s-2006-957624 Papers Pharmacology and Molecular Biology © Georg Thieme Verlag Stuttgart · New York Inhibition of 5α-Reductase and Aromatase by the Ellagitannins Oenothein A and Oenothein B from Epilobium Species B. Ducrey1 , A. Marston1 , S. Göhring2 , R. W. Hartmann2 , K. Hostettmann1 1Institut de Pharmacognosie et Phytochimie, Université de Lausanne, B.E.P., CH-1015 Lausanne-Dorigny, Switzerland 2Universität des Saarlandes, FB 12, Postfach 15 11 50, D-66041 Saarbrücken, Germany Recommend Article Abstract PDF Download Buy Article Abstract Species of the genus Epilobium (Onagraceae) have been investigated for their activity against 5α-reductase and aromatase, two enzymes which are involved in the aetiology of benign prostatic hyperplasia (BPH). Activity-guided fractionation has led to the identification of two macrocyclic ellagitannins, oenothein A (1) and oenothein B (2), as the main constituents responsible for the inhibition of the two enzymes. Quantitation of oenothein B in 10 different species of Epilobium has shown that amounts of up to 14% in the crude plant extracts are possible. key words Epilobium - Onagraceae - ellagitannins - aromatase inhibition - 5α-reductase inhibition - prostate - benign prostatic hyperplasia PDF (336 kb)