酶解鸭骨制取ACE抑制肽工艺条件的优化

Optimization of enzymolysis conditions of ACE inhibitory peptides from duck bones

采用木瓜蛋白酶水解鸭骨制取血管紧张素转化酶(ACE)抑制肽,通过四元二次通用旋转设计优化水解工艺,建立数学模型,分析水解度与ACE抑制率的相关性,并通过不同规格的超滤离心管对酶解产物进行分离。结果表明,木瓜蛋白酶在底物浓度11.5g/100mL,酶底比8000U/g,水解温度60℃,水解时间5.5h,pH值为5.5的条件下,酶解产物的ACE抑制率最高,达到85.71%,水解度为20.81%,且水解度与ACE抑制率显著相关,曲线拟合方程为Y=-157.572+21.215X-0.491X2。超滤后分子量为2ku^3ku的肽段ACE抑制率最高,达到91.67%,半抑制浓度(IC50)为0.927mg/mL,ACE抑制肽回收率为1.99%。

Angiotensin-I converting enzyme（ACE）inhibitory peptides were prepared by papain hydrolysis of duck bones. The hydrolysis conditions were optimized and a mathematical model was established by quadratic general rotation design. The correlation between the degree of hydrolysis and the inhibition rate of ACE was studied. The papain hydrolysates were separated by ultrafiltration centrifuge tubes with different volumes. The results showed that when the substrate concentration was 11.5g/100ml, the ratio ofpapain to substrate was 8000U/g, the hydrolysis temperature, time and pH value were 60℃, 5.5h and 5.5 respectively, the papain hydrolysates had the highest ACE inhibition activity（85.71%）and the degree of hydrolysis was 20.81%. Under above conditions, the degree of hydrolysis showed a significant correlation with the inhibition rate of ACE, whose curve fit equa- tion was as follows： Y=-157.572＋21.215X-0.491X2. After ultrafiltration, the peptides whose molecular weight was from 2ku to 3ku showed highest ACE inhibition activity（91.67%）with a half-maximal inhibitory concentration（IC50）of 0.927mg/ml. The recovery of ACE inhibitory peptides was 1.99%.