Studies On Ultrasonic-assisted Enzymatic Preparation Of ACE Inhibitory Peptides From Mungbean

In this study, used the mung bean as the raw material to make the ACE inhibitorypeptides which had the function to drop the blood pressure. In the procedure of enzymatichydrolysis the protein, we added the UT to assist the enzymatic hydrolysis, according to singlefactor result,using the RSM to process the optimization, The research on the mung beanpeptide material which had been separated and pureed.Took the mung bean as the raw material, choosed the neutral protease pepsin, wood windprotease, Compound protease to do the enzymatic hydrolysis test singly to protein hydrolysisdegree and the ACE inhibition rate as an index screening. The results showed that thecompound protease hudrolysis degree and the ACE inhibition rate were the best. So choosedcompound protease digestion. In this experiment the best of the single factors were: the mungbean to solvent ration1:10, the value of pH at8, ultrasonic power165W, the temperature55℃enzyme amount5%and20min ultrasonic processing time. According to the results of singlefactors, three factors were choosed which were enzymatic quantity, enzymolysis time andultrasonic power were gotten through the optimization of Box-Behnken. the optimumenzymolysis process parameters for the material to solvent was1:10, the value of pH was8,ultrasonic power was154W, the temperature of water was55℃，ultrasonic processing time was20min, enzyme amount was6%and the enzymolysis time1.7h. Under the conditions of thepreparation of mung bean enzymolysis liquid ACE inhibitory rate was87.02%.Took the Mung bean enzymolysis liquid as raw material, By using macroporousadsorption resin to remove the impurities such as inorganic salt and polysaccharide content,three different types of resin for screening, choosed the most suitable resin. For purification ofmung bean peptides. Results showed that amount of adsorption rate and adsorption resinDA201-C were the best. So choosed it. When the concentration of solvent in the process ofstatic adsorption and desorption at10mg/mL, solution pH at5reached the maximumadsorption capacity and adsorption rate. During the dynamic adsorption process, when the flowrate was70ml/h, adsorption rate was the largest. when the concentration was70%ethanolsolution, the components of a maximum ACE inhibitory rate reached90.78%.Used the ultrafiltration segregated the enzymatic hydrolysate of mung bean which waspurified. On the basis of single factor experiment, the optimum parameter with the Orthogonaldesign. The result showed that used the3000intercept molecular weight size of ultrafiltration membrane during ultrafiltration, the ultrafiltrate ACE inhibition rate was the best. The bestprocess conditions of single factors as follows: the temperature was40℃, the time was15min、the value of pH and the ultrafiltration pressure were8and0.08MPa. The optimum parameterwith the Orthogonal design was setting the temperature at40℃, the value of pH was8and theultrafiltration pressure was0.08MPa, then the membrane permeate flux was32.28L/m2h.The material was ultrafiltrate that was treated by ultrafiltration was analyzed thephysicochemical property of ACE inhibitory peptides, and carried out in vivo digestive ofsimulated experiment. The results showed that the ACE inhibitory peptides of mung bean hadthe best emulsion stability at the value of4. the foamability was better under the condition ofacid than alkaline condition, and the best was under the isoelectric point of this protein.Because with the increase of pH, the foaming stability of mung bean peptide became higher.The vivo digestive of simulated experiment showed that ACE inhibitory peptides were notaffected by the gastrointestinal enzymes, and may well play a role in the body.