Affinity purification of angiotensin-converting enzyme inhibitory peptides from Volutharpa ampullacea perryi protein hydrolysate using Zn-SBA-15 immobilized ACE

In this study, a new affinity medium of Zn-SBA-15-immobilized ACE was prepared and applied in the separation of ACE inhibitor peptides from Volutharpa ampullacea perryi protein hydrolysate. Molecular sieve SBA-15 for immobilizing ACE was prepared by hydrothermal crystallization method. Zn2+ was directly adsorbed by SBA-15 to form Zn-SBA-15. ACE was immobilized on Zn-SBA-15 by affinity adsorption. ACE inhibitory peptides were separated by affinity chromatography based on the specific binding force between immobilized ACE and its inhibitors. The bound peptides were released by 2 M NaCl and further purified by reverse-phase high-performance liquid chromatography. Then the amino acid sequence of two peptides with ACE inhibitory activity was identified by MS/MS. Two new ACE inhibitory peptides Ile-Val-Thr-Asn-Trp-Asp-Asp-Met-Glu-Lys (IC50 = 2.08 mM)) and Val-Gly-Pro-Ala-Gly-Arg-Pro-Gly (IC50 = 4.66 mM) were purified from Volutharpa ampullacea perryi protein hydrolysate. The study suggest that the two peptides separated from the Volutharpa ampullacea perryi protein hydrolysate were potent ACE inhibitors and may be used to decrease blood pressure. The significance of the research is to prepare a new affinity medium of Zn-SBA-15 immobilized ACE and apply it in separation of ACE inhibitory peptides from Volutharpa ampullacea perryi protein hydrolysate, which can also provide an effective means to separate the peptides with ACE inhibitory activities from other food sources. It can promote the research and development of antihypertensive active substances.