Preparation and identification of novel angiotensin-I-converting enzyme inhibitory peptides from Moringa oleifera leaf

Moringa oleifera (M. oleifera) is considered a medicinal and edible plant with significant health benefits for humans and animals. It is speculated that the antihypertensive effect of M. oleifera leaf is attributed to the inhibition action of protein-derived bioactive components on Angiotensin-I-Converting Enzyme (ACE). In view of this, combined enzymatic hydrolysis was adopted instead of individual enzymatic treatment to prepare ACE inhibitory peptides, and the hydrolysis conditions were optimized from the perspective of ACE inhibitory activity. Following ultrafiltration, QExactive identification, and in silico screening, four novel ACE inhibitory peptides (IPPAYSK, ILVDR, FFFPK, and LLDPR) were collected. The IC50 values of these peptides ranged from 81.25 to 510.67 μM. In addition, molecular docking simulation and inhibition kinetics were analyzed to explain the inhibition mechanisms. Our study confirms that M. oleifera leaf is a superior source of ACE inhibitory peptides and has potential to serve as ingredients in functional foods for the prevention or management of hypertension.