Technology And Product Development Of Preparation Of Daidzein By Alkalization-high Pressure And Enzymatic Hydrolysis

Soybean isoflavone powder sold by the market was used as sample,The technology of alkalization,high pressure and immobilized enzyme was used together in order to improve the conversion rate of daidzein.Use the activated carbon to remove color from the hydrolysate,purification by macroporous resin,removed the solvent by evaporation,freeze vacuum drying was carried out,in order to prepare the daidzein product with high purityFirstly,the soybean isoflavone powder was pretreated by the frying method of the preliminary research results.Response surface methodology was used to optimize the optimal conditions for sample preparation after alkali hydrolysis.The results are as follows:pH 11,62min,57?,The growth rate of glucoside type is 296.40%,Continue treatment by high pressure process,Through the study of the effect of alkali-high pressure on daidzein transformation,the result shows that:8min,0.2Mpa,1:40(g/mL),and the conversion rate of aglycone is 71.93%.The result shows that alkali-hydrolysis could promote the conversion of acetyl type and C two acyl type into glucoside isoflavone,the accumulation of glucoside type was obtained.After high pressure process,and the conversion rate of glucoside was further improvedThe immobilization of beta glucosidase was carried out with nanomaterials,and study on the effect of it on transformation of glycosides.choose iron oxide,aluminum nitride,silicon dioxide carrier for ?-glucosidase immobilization,relatively better immobilization of the nano-material silica.Then optimize the conditions,Optimal conditions were obtained:45?,PH 5.0,5%and 1h,the enzyme recovery rate is 71.75%.the immobilized enzyme reactor after repeated recycling,used 7 times repeated and substantial loss of activity of immobilized enzyme,immobilized enzyme and free enzyme were stored in Na2HPO4 buffer of pH 5 at 4?respectively,and the residual enzyme activity was measured at different days of storage.after 30 days of storage,the relative enzyme activity of free enzyme was only 20%,while the relative enzyme activity of immobilized enzyme was about 70%.It is concluded that the immobilized enzyme has better storage stability than free enzyme and has a good immobilization effect.It can be used as reference data for industrial production or research experiments.The conditions of hydrolysis of soybean isoflavones by immobilized enzyme were determined by single factor and orthogonal test.The dosage of immobilized enzyme was 8%,pH 5,55?,100min and the conversion rate of glycoside is 23.37%On the basis of the single technology,used soybean isoflavone as sample,The quantity is 181.75mg/g and the conversion rate of daidzein is 90.93%Macroporous resin was used to purify the enzymatic hydrolysate after decolorization,the optimum conditions for the purification of daidzein by macroporous resin were optimized by single factor and response surface methodology.Optimal conditions were obtained:4.2h,4.2h and 1:15(g/mL),according to the optimal conditions.After evaporating solvent,the product was prepared by freeze-drying,the purity is 48.16%.The purity of the hydrolysate increased by 30%compared with that before purification,the purity and conversion rate of the research are improved compared with the previous study,but still not ideal.In the later period,more research about prepare method,purification method and the functional aspects of daidzein should be improvement.