A SIMPLIFIED HPLC METHOD FOR THE DETERMINATION OF PHYTOESTROGENS IN SOYBEAN AND ITS PROCESSED PRODUCTS

By using the proposed procedure, phytoestrogens (daidzein, genistein, coumestrol) can be isolated from soybean and its processed products and subsequently quantitated by HPLC without defatting and cleanup of the samples prior to assay. The samples are extracted with acetonitrile-water, and the extract is filtered through a glass fiber filter. The analytes in the filtrate are in turn separated by HPLC on a C18 column and quantified by spectrometry. The method is sensitive to 2 ppm of isoflavones with UV detection and 0. 5 ppm of coumestrol with fluorescent detection. The recoveries of phytoestrogens in spiked samples ranged between 75 and 110%. The rapidity, simplicity, and low cost of the method make feasible the assay of large numbers of samples in a regulatory laboratory. © 1990, American Chemical Society. All rights reserved.