UV-SPECTROPHOTOMETRIC DETERMINATION OF ISOFLAVONES IN SOYBEAN PRODUCED IN NORTHEAST REGION OF CHINA

The application of triple-wavelength spectrophotometry to the determination of isoflavones in soybean,eliminates interferences of co-existing substances effectively,and gives more reliable analytical results which make the comparative study to have a more reasonable ground.Genistin was used as standard in the UV-spectrophotometric determination,which gave more accurate and precise results as compared with the standard conventionally used in literature.Eleven different species of soybean samples from the northeast region were analyzed by this method,and as shown by the analytical results,two of the species,i.e.the “Kenfeng” and “Zhong dou”,contain higher contents of isoflavones (0.246% and 0.221% respectively),and two other species i.e.the “Dongnong 44 danzhu” and “Dongnong 355”,contain lower contents of isoflavones (0.101% and 0.110% respectively).