酶法制备玉米胚芽ACE抑制肽的研究

Preparation of ACE inhibitory peptides from maize germ by enzymatic hydrolysis

血管紧张素转化酶(ACE)是引起高血压的重要因素,研究一种安全有效的ACE抑制剂十分迫切。以玉米胚芽蛋白为原料,优化玉米胚芽ACE抑制肽的制备工艺。通过单因素试验研究了酶种类、酶解时间、底物浓度、pH值、加酶量、温度对酶解产物水解度和ACE抑制率的影响,选择风味酶为后续试验用酶。在单因素试验的基础上,依据Box-Benhnken原理进行三因素三水平的响应面试验,结果表明影响ACE抑制率的3个因素由主到次依次为pH值、温度和加酶量。确定最佳的酶解工艺条件为底物浓度3%、酶解时间120 min、pH 6、温度40℃、加酶量13300 U/g,此条件下ACE抑制率达到(85.64±0.98)%,与预测值接近。玉米胚芽蛋白ACE抑制肽具有功能因子和天然食物的双重特性,此研究可为降血压药物及相关功能性食品的开发提供理论依据。

Angiotensin converting enzyme( ACE) is an important factor causing hypertension. It is urgent to develop a safe and effective ACE inhibitor.The preparation of ACE inhibitory peptide from maize germ protein was optimized by single factor and response surface tests.The effects of enzyme species,enzymatic hydrolysis time,substrate concentration,pH value,enzyme dosage,and temperature on hydrolysis degree and ACE inhibitory activity of hydrolyzed products were studied,and the flavoring enzyme was selected as the enzyme for subsequent experiments. On the basis of single-factor test,Box-Benhnken principle was used to conduct three-factor and three-level response surface test.The results showed that the effects of various factors on ACE inhibition rate were in this order: pH> temperature > enzyme dosage,and the optimal parameters were as follows: pH 6,temperature 40 ℃,and enzyme dosage 13 300 U/g.After practical verification,the optimum enzymatic hydrolysis conditions were determined as follows: substrate concentration3%,enzymatic hydrolysis time 120 min,pH 6,temperature 40 ℃,and enzymatic dosage 13 300 U/g. Under this condition,ACE inhibition rate reached( 85. 64±0. 98) %,which was close to the predicted value.The ACE inhibitory peptides of maize germ protein has the dual characteristics of functional factor and natural food. This study will provide a theoretical basis for the development of antihypertensive drugs and related functional food.