The lignan glycoside, tracheloside, was isolated from seeds of Carthamus tinctorius (Compositae) as an anti-estrogenic principle against cultured Ishikawa cells by employing a bioassay-linked HPLC-ELSD method. Tracheloside significantly decreased the activity of alkaline phosphatase (AP), an estrogen-inducible marker enzyme, with an IC(50) value of 0.31 microg/ml, a level of inhibition comparab...