【摘要】 通过测定鲢Hypophthalmichthysmolitrix头酶解物对血管紧张素转化酶(ACE)的抑制率(I),确定了蛋白酶酶解鲢头制取ACE抑制肽(ACEI)的酶种及其最佳酶解工艺条件,并用SephadexG-15凝胶柱对酶解物进行分离,测定酶解物中ACE抑制肽的相对分子质量分布。结果表明:在胰蛋白酶、木瓜蛋白酶、胃蛋白酶、枯草杆菌蛋白酶和复合风味蛋白酶5种酶中,胃蛋白酶为酶解鲢头制备ACE抑制肽的理想蛋白酶;其最佳酶解工艺条件为温度37℃、pH2 0、酶解时间3h、酶的质量分数为1 4%、底物浓度w(原料)∶w(水)=1∶3,在该条件下得到的酶解物对ACE的抑制活性最强,其I=83 58%;在最佳酶解工艺条件下得到的酶解物经层析分离,在最大洗脱峰处得到的ACE抑制肽抑制活性最高,其I=86 72%,相对分子质量为1096。更多还原

【Abstract】 The optimal conditions of preparation of hydrolysates from a silver carp (Hypophthalmichthys molitrix) head with the maximal inhibition of angiotensin converting enzyme (ACE) were determined by measuring the inhibition effects (I) of the hydrolysates. Isolation of the hydrolysates and the molecular weight of the peptide were measured by Sephadex G-15. The results showed that there were five enzymes(trypsase, papain, pepsin, subtilisin, flavourzyme) that can hydrolyze silver carp head into hydrolysates. The pepsin had the maximal activity of 83.58%. The optimal hydrolysis conditions for pepsin were as the following: temperature 37℃, pH 2.0, 3 h period, E/S 1.4% and substances∶water = 1∶3. The molecular weight of the peptide with the highest inhibition activity was 1 096Da.更多还原