Isolation Of Tempe Isoflavones And Relationship Between Isoflavones Structure And Bioactivity

College of Food Science and Technology ,Nanjing Agriculture University ABSTRACT 1.Three isoflavones including genistein,daidzein and glycitein were extracted and isolated from Tempe by silica and polyamide chromatography . Neither 6,7,4?trihy drocy isoflavone nor isoflavones glycoside was obtained in this process. Therefore the isoflavones in Tempe was mainly consist of aglycones. The results showed that the isollavone glycosides in soybeans were hydrolyzied to aglycones by P -glucosidase. The study also showed that the genistein may be changed into glycitein during the extraction and purification of isoflavones when methanol was used as solvent. Two isoflavones gtycosides were extracted and isolated from soybeans by reverse chromatography. The isofiavones in soybeans were mainly consist of glycosides and a little aglycones . Daidzin has similar chemical polarity with genistin , so it is difficult to isolate 2.Three types of cancer cell lines including MCF-7~ Hela and HO-8901 were treated by genistein,daidzein,glycitein,genistin ,daidzin,mixture of genistein and daidzein( equal in mci) and mixture of genistin and daidzin (equal in mel) respectively. Genistein at lO4rnol/L provided 63.08% of inhibition and 1C50=8.47X iO~ mol/L on breast cancer MCF-7 cell, 58.042% of inhibition and 1C509.447X l0~ mol/L on Hela cell, 67.70% of inhibition and 1C50=8.47X l0~ mol/L on HO-9810 cell. Daidzein at l0~mo1 IL provided 63.08% of inhibition and 1C508.47)< l0~ molIL on HO-98l0 cell. Mixture of genistein and daidzein( equal in mel) at lO4mol IL provided 73.132% of inhibition and 1C50?.47 X l0~ mauL on breast cancer MCF-7 cell , 92.432% of inhibition and 1C50=8.47X io~ mol/L on cancer cell , 86.20% of inhibition and IC50~8.47X l0~ moi/L 昽n cancer cell. Daidzein cooperates with genistein in antitumor. 90 Tempe isoflavones had stronger antitumor activity than soybean isoflavones, Gensitein showed the most extensive and strongest antitumor activity , daidzein only had effect on HO-8910 cell line and isoflavone glycosides had no antitumor activity. However genistein and daidzein had higher IC50 value indicating that they can抰 kill cancer cell directly , but they may inhibit cancer cells by antioxidant and receptor way. Tempe isoflavones aren抰 good antitumor drugs but Ternpe is a good care health food in assist antitumor The antioxidant experiments showed that bioactivity of soybean isoflavones was mainly owe to genistin and genistein and that genistein had stronger bioactivity than genistin. 3. The change of isoflavones in soybean were determined with HPLC during soybean fermention process. Most of isoflavones glycosides of soybean (75%) were changed into aglycones ,within 24h the isoflavone in soybeans was mainly consist of daidzin and genistin (97%) and mainly consist of daidzein and genistein (85%) in Tempe. The rnot concentration of daidzein and genistein in Tempe was 52.25% higher than that in soybean~ for other kinds of soybean isoflavones may be change into daidzein and genistein during soybean ferrnention. 4.Tempe fl -glucosidase was purified from liquid fermentation of Tempe. Its Mr was 77000S, optinal pH was 4-h, Moderate temperature was 4O..5O~C. The enzyme can h...