高粱碱溶蛋白ACE抑制肽的制备及其稳定性研究

Preparation and Stability of ACE Inhibitory Peptides Derived from Sorghum Protein

以高粱为原料,通过碱法提取制备高粱碱溶蛋白,利用不同蛋白酶对其进行酶解,结果表明Alcalase碱性蛋白酶水解高粱蛋白得到的水解产物水解度和血管紧张素转化酶(ACE)抑制率最高。在此基础上进一步考察了碱性蛋白酶酶量、pH值、温度、反应时间这4个因素对水解产物ACE抑制率的影响,并通过响应面实验优化酶解条件,得到Alcalase碱性蛋白酶水解高粱碱溶蛋白制备ACE抑制肽最优工艺为:酶解温度55.5 ℃,酶解时间1.68 h,pH值7.95,酶量2 360 U/g,此条件下实测ACE抑制率达到75.98%,该ACE抑制肽具有良好的热稳定性和酸碱稳定性,并且在体外经胃肠道酶系消化酶解后,依然能保持良好的抑制活性。

Sorghum alkali soluble protein was extracted from sorghum by alkali method. Alcalase enzyme was selected to be the best one for the enzymatic hydrolysis through the comparison of hydrolysis degree and ACE inhibition rate. On this basis, the effects of alcalase enzyme concentration, pH, temperature and reaction time on the ACE inhibition rate of the hydrolysate were investigated by single factor test. Furthermore, taking ACE inhibitory rate as response value, Box-Behnken design and response surface methodology (RSM) were used to optimize the enzymolysis conditions. The results showed the optimum conditions: the amount of enzyme was 2 360 U/g, pH 7.95, enzymatic temperature at 55.5 ℃ for 1.68 h, and the inhibitory rate of ACE was 75.98%. Meanwhile, the stability of Sorghum ACE inhibitory peptides was studied. Sorghum ACE inhibitory peptides had good resistance to thermal, acid, alkaline and intestinal enzymes digestion.