Extraction, Identification, and Preliminary Investigation of the Antihypertensive Mechanism of ACE-Inhibitory Peptides from Apocynum venetum L.

In this study, Apocynum venetum was employed as the raw material to optimize protein extraction and enzymatic hydrolysis processes for the preparation of highly active angiotensin-converting enzyme (ACE)-inhibitory peptides, achieving an ACE inhibition rate of 92.34%. Multispectral analyses and microstructural characterization demonstrated that enzymatic hydrolysis induced the unfolding of protein secondary structures, resulting in a looser and more porous morphology enriched with characteristic amino acids. A total of 2567 peptide sequences were identified by LC–MS/MS, among which 18 potential bioactive peptides were screened. Molecular docking analysis revealed that these peptides interact with the active site of ACE primarily through hydrogen bonding and hydrophobic interactions, with WLRDFL exhibiting the strongest binding affinity. This study systematically elucidates the structural characteristics and antihypertensive molecular mechanisms of ACE-inhibitory peptides derived from Apocynum venetum, providing both theoretical insights and experimental support for the development of natural antihypertensive functional foods and the high-value utilization of this plant.