Department of Biotechnology, ‡Department of Natural Science, Division of Food Bioscience, #College of Medicine Institute of Biomedical Science and Technology, and ⊥Korea Nokyong Research Center, Konkuk University , Chungju 380-701, Korea.
J Agric Food Chem. 2012 Oct 10;60(40):10035-40. doi: 10.1021/jf3023172. Epub 2012 Sep 28.
An angiotensin I-converting enzyme (ACE) inhibitory peptide was isolated and identified from hydrolysates of duck skin byproducts. Duck skin byproducts were hydrolyzed using nine proteases (Alcalase, Collagenase, Flavourzyme, Neutrase, papain, pepsin, Protamex, trypsin, and α-chymotrypsin) to produce an antihypertensive peptide. Of the various hydrolysates produced, the α-chymotrypsin hydrolysate exhibited the highest ACE inhibitory activity. The hydrolysate was purified using fast protein liquid chromatography (FPLC) and high-performance liquid chromatography (HPLC). The amino acid sequence of the ACE inhibitory peptide was identified as a hexapeptide Trp-Tyr-Pro-Ala-Ala-Pro, with a molecular weight of 693.90 Da. The peptide had an IC50 value of 137 μM, and the inhibitory pattern of the purified ACE inhibitor from duck skin byproducts was determined to be competitive by Lineweaver-Burk plots. In addition, the peptide was synthesized and the ACE inhibitory activity was verified in vivo. Spontaneously hypertensive rats (SHR) exhibited significantly decreased blood pressure and heart rate after peptide injection. Taken together, the results suggest that Trp-Tyr-Pro-Ala-Ala-Pro may be useful as a new antihypertensive agent.
从鸭皮副产物的水解产物中分离和鉴定出一种血管紧张素转化酶（ACE）抑制肽。使用九种蛋白酶（碱性蛋白酶、胶原酶、风味蛋白酶、中性蛋白酶、木瓜蛋白酶、胃蛋白酶、蛋白酶、胰蛋白酶和α-糜蛋白酶）水解鸭皮副产物以产生具有降压作用的肽。在产生的各种水解产物中，α-糜蛋白酶水解产物表现出最高的 ACE 抑制活性。使用快速蛋白液相色谱（FPLC）和高效液相色谱（HPLC）对水解产物进行纯化。ACE 抑制肽的氨基酸序列被鉴定为六肽 Trp-Tyr-Pro-Ala-Ala-Pro，分子量为 693.90 Da。该肽的 IC50 值为 137 μM，通过 Lineweaver-Burk 作图确定从鸭皮副产物中纯化的 ACE 抑制剂的抑制模式为竞争性。此外，还合成了该肽并在体内验证了其 ACE 抑制活性。肽注射后自发性高血压大鼠（SHR）的血压和心率明显降低。综上所述，结果表明 Trp-Tyr-Pro-Ala-Ala-Pro 可能可用作新型抗高血压药。
