Novel ACE inhibitory peptides derived from whey protein hydrolysates: Identification and molecular docking analysis

Angiotensin I-converting enzyme (ACE) plays a significant role in the regulation of blood pressure via generating angiotensin II (Ang II). Using natural inhibitors to block the activity of ACE is an alternative method to minimize the side effects of commercial drugs, and is a major goal of hypertension management. This study detected the presence of ACE inhibitory peptides in whey protein hydrolysate. The whey protein hydrolysate was separated sequentially by ultrafiltration and RP-HPLC. LC-MS/MS revealed the amino acid sequences of the fractions and four potential ACE inhibitory peptides were selected (PQVSTPTL, MPGP, PMHIR, PPLT) for synthesis. IC50 values of these four peptides were 86 ± 8, 179 ± 4, 90 ± 6, and 168 ± 4 μM, respectively. Then, molecular docking analysis was used to assess how these peptides interact with ACE. PQVSTPTL exhibited the lowest binding energy (−6.64 kcal/mol) with the ACE molecule. These four reported peptides were with no allergenicity nor toxicity. These results indicated that whey protein hydrolysate could be a suitable resource for obtaining novel inhibitory peptides against ACE and provides information for obtaining novel ACE inhibitors for hypertension management.