羧肽酶A/B水解虾副产物制备ACE抑制肽

Preparation of Angiotensin I-Converting Enzyme Inhibitory Peptides from Shrimp Byproducts Hydrolyzed by Carboxypeptidase A/B

为了获得血管紧张素转化酶（ACE）抑制肽,使用α-胰凝乳蛋白酶对虾副产物进行预酶解,再选择羧肽酶A/B进行酶解,通过透析和凝胶层析纯化后,测定分离肽的ACE抑制活性。通过检测水解度,确定α-胰凝乳蛋白酶的最优水解时间为4h,羧肽酶A/B最优水解时间为6h。两步酶解产物的ACE半抑制浓度（IC50）值为6.39mg/mL。通过透析,得到〈500Da和500～1 000Da 2个抑制活性更高的组分,IC50分别为1.69和2.87mg/mL。进一步通过Sephadex G-15凝胶层析分离,得到4个IC50值小于0.2mg/mL的组分,其中组分F8最低,为0.134mg/mL,显示了较高的ACE抑制活性。该结果验证了羧肽酶A/B酶解可制备出高活性ACE抑制肽。

To prepare angiotensin I-converting enzyme（ACE）inhibitory peptides,shrimp byproducts were successively hydrolyzed by α-chymotrypsin and carboxypeptidase A/B.The hydrolysates were then separated and purified by dialysis and gel-filtration chromatography.Based on the hydrolysis degree,the optimal hydrolysis time was 4hforα-chymotrypsin and 6hfor carboxypeptidase A/B.The IC50 value of the final hydrolysate was 6.39mg/mL.Fractions of molecular weight〈500Da（IC50=1.69mg/mL）and 500-1000Da（IC50=2.87mg/mL）were obtained by dialysis.These two fractions were further separated into 8fractions by sephadex G-15gel-filtration chromatography,four of them had IC50 values lower than 0.2mg/mL,and that of the lowest one（F8）was 0.134 mg/mL.The result proved that the enzymolysis of carboxypeptidase A/B could produce peptides with high ACE inhibitory activity.