Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China.
Key Laboratory of Functional Dairy, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
Molecules. 2020 Jun 30;25(13):3009. doi: 10.3390/molecules25133009.
Identifying DPP-IV inhibitory peptides from dietary protein has attracted increased attention. In the present study, bovine α-lactalbumin hydrolysates were generated by alcalase for various hydrolysis times, and DPP-IV inhibitory activity of these hydrolysates was determined. The 4 h hydrolysates displayed the most potent DPP-IV inhibitory activity, with DPP-IV inhibition rate of 82.30 ± 1.39% at concentration of 1.0 mg/mL. DPP-IV inhibitory peptides were isolated from the 4 h-hydrolysates with gel filtration chromatography and reversed-phase high-performance liquid chromatography (RP-HPLC). Using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI MS/MS), two DPP-IV inhibitory peptides were identified, and their amino acid sequences were Glu-Leu-Lys-Asp-Leu-Lys-Gly-Tyr (ELKDLKGY) and Ile-Leu-Asp-Lys-Val-Gly-Ile-Asn-Tyr (ILDKVGINY), respectively. Furthermore, molecular docking analysis showed that peptides ELKDLKGY and ILDKVGINY could form hydrogen bonds, pi-cation interactions, and salt bridges with DPP-IV. These findings indicated that bovine α-lactalbumin may be a potential source of natural DPP-IV inhibitor.
从膳食蛋白质中鉴定 DPP-IV 抑制肽引起了越来越多的关注。本研究采用碱性蛋白酶水解牛α-乳白蛋白，得到不同水解时间的水解产物，并测定其对 DPP-IV 的抑制活性。4 h 的水解产物显示出最强的 DPP-IV 抑制活性，在浓度为 1.0 mg/mL 时，对 DPP-IV 的抑制率为 82.30±1.39%。采用凝胶过滤色谱和反相高效液相色谱（RP-HPLC）从 4 h 水解产物中分离出 DPP-IV 抑制肽。采用液相色谱-电喷雾串联质谱（LC-ESI MS/MS）鉴定出两种 DPP-IV 抑制肽，其氨基酸序列分别为 Glu-Leu-Lys-Asp-Leu-Lys-Gly-Tyr（ELKDLKGY）和 Ile-Leu-Asp-Lys-Val-Gly-Ile-Asn-Tyr（ILDKVGINY）。此外，分子对接分析表明，肽 ELKDLKGY 和 ILDKVGINY 可以与 DPP-IV 形成氢键、π-阳离子相互作用和盐桥。这些发现表明牛α-乳白蛋白可能是天然 DPP-IV 抑制剂的潜在来源。
