Chemical Determination of Isoftavones

Recent developments in ruminant nutrition by using estrogenic additives to stimulate the rate of gain and feed efficiency of beef cattle (Burroughs et al. 1954) indicated the important role of feeds and forages containing estrogenic substances. Forages such as clover and alfalfa have been shown to contain small amounts of estrogenic substances (Cheng et al. 1953a). An isoflavone derivative, genistein, isolated from soybean oil meal was found to be estrogenic by the mouse uterine weight assay (Cheng et al. 1953b). Several isoflavone compounds have been synthesized chemically (Yoder et al. 1954) and they have been shown to be estrogenic also (Cheng et al. 1954). It appears then the total content of isoflavones in plant material may be related to its estrogenic potency. Unfortunately, there are no satisfactory chemical methods available for the estimation of isoflavones in feeds. The objective of this communication is to describe a procedure in which the total isoflavone content of a plant can be determined chemically