摘要
To obtain Angiotensin-I-Converting Enzyme(ACE)inhibition peptides with Zn-chelating capacity,millet bran albumin hydrolysates(MBAH)were subjected to Sephadex G-15 gel and reverse phase-high liquid performance chromatography,and UPLC-ESI-MS/MS analysis.Five oligopeptides including Val-Gly-Ser-Asp-Gly-Leu(VGSDGL),Thr-Gly-His-Gly-Val-Ala(TGHGVA),Gly-Cys-His-His-Tyr(GCHHY),Leu-Val-Glu-Ala-Val-Pro-Arg-Gly(LVEAVPRG)and Val-Leu-Ala-Gln-Glu-Glu(VLAQEE)were identified in MBAH.Of these,only pentapep-tide GCHHY showed both ACE-inhibitory activity(IC50:134.78μmol/L)and Zn-chelating capacity(14.16 mg/g).Molecular docking and inhibition kinetics showed that GCHHY was a competitive inhibitor of ACE,because it could bind with Lys511 of ACE which belongs to the central S2 pocket.Moreover,GCHHY can affect zinc tetrahedral coordination in ACE through binding with Glu411 and His383.The sulfhydryl,amino and carboxyl groups of GCHHY can bind with zinc ions.Under the gastrointestinal digestion,the ACE-inhibitory activity of GCHHY was relatively stable,and the zinc solubility of GCHHY-Zn complexes was more stable than zinc sulfate(P<0.05).In addition,both GCHHY and GCHHY-Zn complexes lowered the diastolic blood pressure and systolic blood pressure of spontaneous hypertensive rats at dose of 50-200 mg/kg body weight.These results suggested the potential applications of millet albumin peptides as ingredients for antihypertension or zinc fortification.
基金
supported by the Natural Science Foundation of Shanxi Province,China(202203021221139)
Shanxi Province Graduate Education Innovation Project,China(No.2023SJ180).
