Microencapsulated and controlled-release formulations of isoflavone from enriched fractions of soy and other plants

There is provided an orally-administrable formulation for the controlled release or stable storage of a granulated isoflavone-enriched fraction or mixture of such fractions, comprising at least one granulated isoflavone-enriched fraction and at least one carrier, diluent or excipient therefor. Preferably, the formulation is characterized in that the total in vitro dissolution time of said formulation required for release of 75% of the active ingredients available from the formulation is between about 4 and about 18 hours, as determined by the U.S.P. XXIII paddle method at a paddle speed of 75 rpm, using simulated intestinal fluid without the digestive enzymes normally found in intestinal fluid, at pH 6.8, and a temperature of 37° C. A process for the preparation of such a formulation is also provided.