Production of isoflavone

PURPOSE: To obtain the subject isoflavone which shows considerable antioxidant behavior against and fats in foods and cosmetic can be obtained in a high yield, economically by extracting grinding soya beans with alcohol, extracting the obtained crude extract by water immiscible-organic solvent, and separating it. CONSTITUTION: By extracting the ground soya beans by alcohol, bufferizing the obtained crude extract to pH 6-9 buffer solution, extracting the buffer solution by water immiscible organic solvent, recovering the water phase, acidifying it to pH 2.5-4, extracting the acid it water phase by the said organic solvent, recovering the organic phase, neutralizing it and separating the residual compound, the objective isoflavone can be obtained. Furthermore, it is desirable that the ground soya beans are heated at 70-90°C for 50-100 minutes and extracted by 70-90% methanol aqueous solution and the said organic solvent is butanol. COPYRIGHT: (C)1991,JPO