Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China.
Medical College, Guangxi University of Science and Technology, Liuzhou 545006, China.
Mar Drugs. 2021 Mar 23;19(3):177. doi: 10.3390/md19030177.
Angiotensin-I-converting enzyme (ACE) inhibitory peptides derived from marine organism have shown a blood pressure lowering effect with no side effects. A new affinity medium of FeO@ZIF-90 immobilized ACE (FeO@ZIF-90-ACE) was prepared and used in the purification of ACE inhibitory peptides from Wakame () protein hydrolysate (<5 kDa). The FeO@ZIF-90 nanoparticles were prepared by a one-pot synthesis and crude ACE extract from pig lung was immobilized onto it, which exhibited excellent stability and reusability. A novel ACE inhibitory peptide, KNFL (inhibitory concentration 50, IC = 225.87 μM) was identified by affinity purification using FeO@ZIF-90-ACE combined with reverse phase-high performance liquid chromatography (RP-HPLC) and MALDI-TOF mass spectrometry. Lineweaver-Burk analysis confirmed the non-competitive inhibition pattern of KNFL, and molecular docking showed that it bound at a non-active site of ACE via hydrogen bonds. This demonstrates that affinity purification using FeO@ZIF-90-ACE is a highly efficient method for separating ACE inhibitory peptides from complex protein mixtures and the purified peptide KNFL could be developed as a functional food ingredients against hypertension.
从海洋生物中提取的血管紧张素转化酶（ACE）抑制肽具有降低血压的作用，且无副作用。本研究制备了一种新型亲和介质 FeO@ZIF-90 固定化 ACE（FeO@ZIF-90-ACE），并用于从裙带菜（Undaria pinnatifida）蛋白水解物（<5 kDa）中纯化 ACE 抑制肽。通过一锅合成法制备了 FeO@ZIF-90 纳米粒子，并将其粗提的猪肺 ACE 固定化在其上，该亲和介质具有优异的稳定性和可重复使用性。通过 FeO@ZIF-90-ACE 亲和纯化结合反相高效液相色谱（RP-HPLC）和 MALDI-TOF 质谱法，鉴定出一种新型 ACE 抑制肽 KNFL（抑制浓度 50，IC = 225.87 μM）。Lineweaver-Burk 分析证实 KNFL 呈非竞争性抑制模式，分子对接表明其通过氢键与 ACE 的非活性部位结合。这表明，使用 FeO@ZIF-90-ACE 的亲和纯化是一种从复杂蛋白质混合物中分离 ACE 抑制肽的高效方法，并且纯化的肽 KNFL 可作为抗高血压的功能性食品成分进行开发。
