Separation,Purification And Activity Of Ace Inhibitory Peptides From Scallop Skirts

In order to improve the utilization of the scallop skirt,the optimization of the protease hydrolysis,the structure of the ACE-inhibitory peptide was obtained by separating and purifying the enzymatic hydrolysate,and the hypertensive activity was verified.The main research contents and results are as follows:1.Scallop skirts were used as raw materials and enzymed by pepsin,papain,acid protease,neutral protease,and alkaline protease,respectively,andthe activity of ACE inhibitory of enzymatic hydrolysis of scallop skirts was investigated.The ACE inhibition rate of the papain hydrolysates was the highest,which was 71.25%.According to the results of the single factor experiment and the orthogonal test,the optimum enzymolysis process conditions were determined as follows:solid-liquid ratio?g/mL?1:3,enzyme amount 2.0%,enzymolysis temperature 60°C,hydrolysis time 1 h,pH 7.0.2.The enzymatic hydrolysis of scallop skirt was separated by the Sephadex LH-20 column,and F5,F6,F7 were found with ACE inhibitory activity,and then separated with RP-HPLC?20%acetonitrile?.The components of F5-3,F7-2,and F7-4were found with ACE inhibitory activity.Further purification were completed with RP-HPLC?10%acetonitrile?,and the ACE inhibitory activity were found in F5-3-3and F7-4-3,while the eight components eluted from F7-2 all had ACE inhibitory activity.Finally,F5-3-3 was identified by mass spectrometry.The sequence of the ACE-inhibitory peptide was Val-Trp?VW?and the molecular weight was 303.17 Da.The IC₅₀ of the ACE-inhibitory peptide was 86.9?mol/L.3.The blood pressure lowering activity of ACE inhibitor peptides derived from scallop skirts was measured.Through an ultrafiltration membrane,the scallop skirt enzymatic liquid entrapped into samples of different molecular weight range,wherein the molecular weight range of 3KDa¹KDa hydrolysates showed higher ACE inhibitory activity,with IC₅₀ value of 0.88 mg/mL.The portion of the active peptide was administered by intragastric administration and SBP was measured by tail-cuff method.The results showed that active peptide could significantly reduce the SBP of SHR.Compared with SBP of blank control group after 9 days of administration?172±7 mmHg?,it was a significant difference?P<0.01?.On the 28th day,the SBP decreased to 161±3 mmHg,but the antihypertensive effect was lower than that of the positive control group;on the 7th day after drug withdrawal,the blood pressure value of the administration group was 169±5 mmHg,compared with the control group SBP showed a very significant difference?P<0.01?;while scallop skirts active peptide on the weight gain of SHR rats also have a certain role.On the 28th day after discontinuation,the serum levels of ACE,Ang II,ATG,and ALD in SHR rats were measured and found to be lower than the blank control group.Compared with the positive control group,ACE in the serum of the active peptide administration group was higher than that of the SHR serum.The expression levels of Ang II and ATG were slightly higher,but the expression level of ALD was relatively lower.