Study On One Kind Of Milk With ACE Inhibitory Activity

Milk protein resources are rich.They have good nutritional value,and they also considered as an important source of many bioactive peptides.ACE inhibitory peptides with anti-hypertensive activity(Angiotensin-I converting enzyme inhibitory peptide,ACEI peptide)were obtained by hydrolyzing milk protein with protease.This kind of peptide were formed by 2~10 amino acid residues.It can block the generation of angiotensin II through competitive combination,which has the function of raising blood pressure,meanwhile promote the formation of the peptide and enkephalin,which has the function of lowering blood pressure.Results of Traditional Chinese medicine research had confirmed a large number of Chinese medicine with the regulation of blood pressure,which is rich in medicinal resources.Study the compatibility of Chinese herbal medicine with milk protein ACE inhibitory peptides has theoretical and practical significance for developing functional dairy products which has auxiliary health care effect.The main contents of this study are:(1)On the basis of the skim milk,the inhibitory activity of ACE was evaluated by the reaction of single enzyme and double enzyme,and the reaction solution containing enzyme was used as the reaction reagent.Take the ACE inhibitory activity of the enzyme solution as index,the optimal protease was screened,and the enzymatic hydrolysis conditions were optimized for producing the enzyme with high ACE inhibitory activity;(2)ACE enzyme was used as the target to evaluate the inhibitory effect of 15 kinds of Chinese herbal medicine on ACE inhibitory activity.Screen out the Chinese herbal medicine with high inhibition activity of ACE;(3)Formula of high ACE inhibitory activity were obtained by mixed milk protein hydrolysate and the selected Chinese herbal extracts;(4)Study on the formula of inhibitory effect of ACE.The test results are as follows:(1)Through the comprehensive comparison of single enzyme and double enzyme catalyzed hydrolysis.It was found that trypsin had the strongest effect as the research object.By using the four factor and three level response surface design,the enzymatic hydrolysis conditions of trypsin hydrolyzed skim milk were optimized by ACE inhibition activity,The best reaction condition is: The substrate concentration7g/100 m L,enzymolysis time 6 h,the amount of enzyme 5%,enzymatic hydrolysis temperature 31?,p H 6.9,under the experimental conditions,defatted milk solution ACE inhibition rate was 58.51%;(2)The ACE inhibitory activity of 15 common Chinese herbs with anti-hypertensive effects was compared and evaluated.The activity of ACE was evaluated by 15 kinds of Chinese herbal medicines: Hawking> Cassia> Lycium> Campanulaceae> White peony> Astragalus> Ginkgo biloba> Gardenia> Cortex Moutan> radix polygonati officinalis> Ginseng> Bergamot> Mulberry leaves> Chrysanthemum> Yam.The ACE inhibition rate increased to 52.52% when the hawthorn extract and cassia seed extract were mixed at 2:1.The final ratio of mixture of hawthorn extract and cassia seed extract was 2:1.(3)Mixed the hydrolysate of milk protein and the extract of Chinese herbal medicine.The results showed that the inhibitory activity of ACE was maximum when both of them were 1:1;(4)The formula was studied through the sensory evaluation of the products.The results showed that the best formula of ACE to inhibit the activity of milk was:citric acid0.4%,CMC-Na 0.5%,emulsifier 0.4%,white granulated sugar 10%.