PLANT CONSTITUENTS INTERFERING WITH HUMAN SEX HORMONE-BINDING GLOBULIN - EVALUATION OF A TEST METHOD AND ITS APPLICATION TO URTICA-DIOICA ROOT EXTRACTS

A lest system is described, which allows the search for compounds inte rfering with human sex hormone-binding globulin (SHBG) even in complex plant extracts. The method has been evaluated and applied to Urtica d ioica root extracts. The lignan secoisolariciresinol (5) as well as a mixture of isomeric (11E)-9,10,13-trihydroxy-11-octadecenoic and (10E) -9,12,13-trihydroxy-10-octadecenoic acids (3 and 4, resp.) were demons trated to reduce binding activity of human SHBG. Methylation of the mi xture of 3 and 4 increased its activity about 10-fold.