Soy Germ Isoflavone Extract,

A process for extracting and purifying isoflavones from soybean germ was studied in this paper. The process includes extraction of total isoflavones and hydrolyzation of soybean isoflavone by solid acid catalyst.In the experiments of extraction of total isoflavones, five factors were studied: temperature, extracting time, concentration of solvent and amount of solvent. With the extraction efficiency of total isoflavones and the selectivity of extraction as study targets, the optium extraction conditions were as followed: solvent 60% ethanol, temperature 50℃, solvent volume to sobean germ weight 6:1, extracting for 3times, 60min 10min , 10min respectively. Extraction efficiency of total isoflavones was about 92%.In the experiments of fixed bed process, soybean isoflavone glucoside can be hydrolyzed into isoflavone aglucone with methanol in a fixed bed filled with solid acid catalyst(Nankai Chemical Factory, D72). Conversion of isoflavones is about 90%. The effect of temperature, contact time, concentration of methanol and proportion of solvent to material on conversion was studied. The results show that enhancing temperature and prolonging the contact time are favor of the reaction, and the ratio of methanol to water is appropriately 1:2.During the process of refining of isoflavones from the extraction, methods such as chromatogram, extraction, deposition were researched. Content of isoflavone was as high as 40%, and recovery percent of isoflavone based on soybean germ was about 50%. Analytical method for total isoflavones and isoflavone aglucone was established.