Tianjin Key Laboratory of Food Biotechnology, College of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin, 300134, China.
Tianjin Key Laboratory of Food Biotechnology, College of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin, 300134, China.
Peptides. 2018 Jan;99:161-168. doi: 10.1016/j.peptides.2017.09.021. Epub 2017 Oct 4.
In this study, we identified a novel angiotensin-I-converting enzyme (ACE) inhibitory peptide, YQKFPQYLQY (YQK), derived from bovine casein. Casein was hydrolyzed using pepsin and trypsin. The target peptide, YQK, was separated from the hydrolysate by ultrafiltration and Sephadex G-15chromatography. The IC value of YQK was 11.1μM. YQK retained its ACE inhibitory activity under various temperature and pH conditions. It was also stable against the digestive enzymes pepsin and trypsin. The Lineweaver-Burk plot suggested that the inhibitory mode of YQK was competitive. Furthermore, its antihypertensive effects in spontaneously hypertensive rats (SHRs) also revealed that oral administration of YQK can significantly decrease systolic blood pressure. These results suggested that YQK may have potential applications in functional foods or pharmaceuticals as an antihypertensive agent.
在这项研究中，我们从牛酪蛋白中鉴定出一种新型的血管紧张素转化酶（ACE）抑制肽，YQKFPQYLQY（YQK）。酪蛋白用胃蛋白酶和胰蛋白酶水解。目标肽 YQK 通过超滤和葡聚糖凝胶 G-15 层析从水解物中分离出来。YQK 的 IC 值为 11.1μM。YQK 在各种温度和 pH 条件下保持 ACE 抑制活性。它对胃蛋白酶和胰蛋白酶等消化酶也稳定。Lineweaver-Burk 作图表明，YQK 的抑制模式为竞争性。此外，其在自发性高血压大鼠（SHRs）中的降压作用也表明，口服 YQK 可显著降低收缩压。这些结果表明，YQK 可能作为一种抗高血压药物在功能性食品或药物中有潜在的应用。
