Production,Isolation And Purification Of Bovine Collagen Peptides And Their ACE Inhibitory Effect

Angiotensin-I Convertion Enzyme(ACE;EC 3.4.15.1)plays an important physiological role in the regulation of blood pressure and genesis of hypertension,by virtue of the rennin-angiotensin system.Previously,many studies proved that the inhibition of ACE can reduce the generation of angiotensin II,which has the effect on promoting the blood pressure.What's more,angiotensin converting enzyme inhibitors(ACEI)were made success in clinic of control hypertension which made it clear that ACEI has the effect on regulating blood pressure.In addition,The peptides derived from food proteins are considered to be milder and safer compared with synthetic drugs;furthermore,these peptides usually have multifunctional properties and are easily absorbed.Therefore,the aim of this study was to search for ACE inhibitors derived from food protein.The conclusions are as follows:Firstly,the enzymesation processes towards bovine skin were optimized.The results showed that the complex enzymes method with pepsin and alcalase had the best effect.And the ACE inhibitory activity was much higher with the IC50 value of 0.168mg/ml,compared with monoenzyme hydrolysate,9.6 times with alcalase,14.2 times with pepsin,and 16.1 times with flavorzyme,respectively.Secondly,the hydrolysate was further isolated,purified and identificated.Finally,two novel peptides with high ACE inhibitory activity were gained,with the amino acid sequence of ISVPGPM(IC50=24.3?M=0.017mg/ml)and LGPVGNPGPA(IC50=87.8.M=0.077mg/ml).Finally,the stability of these two peptides against gastrointestinal proteased was assessed in vitro,with pepsin,trypsin and chymotrypsin.We found that some of the shorter peptides after hydrolised still had the activity of ACE inhibition.