Angiotensin I-converting enzyme, dipeptidyl peptidase-IV, and alpha-glucosidase inhibitory potential of hazelnut meal protein hydrolysates

The objective of this study was to determine the bioactive potential of hazelnut meal protein hydrolysates. Hazelnut meal protein isolate was hydrolyzed using Alcalase and Trypsin + Chymotrypsin to 23.5% and 13.7% degrees of hydrolysis, respectively. The peptide fractions (< 5 kDa and > 5 kDa) were screened for the in vitro inhibition of angiotensin I-converting enzyme (ACE), dipeptidyl peptidase-IV (DPP-IV), and alpha-glucosidase activities. Peptide fractions > 5 kDa showed a higher potency to inhibit ACE (IC50 = 0.10-0.13 mg/mL), whereas peptide fractions < 5 kDa were more effective in inhibiting DPP-IV (IC50 = 0.37-0.45 mg/mL) and alpha-glucosidase (IC50 =3.62-3.89 mg/mL), with no significant difference in treatment with Alcalase and Trypsin + Chymotrypsin. The results of the study showed that hazelnut meal protein is a potential source of bioactive peptide delivery and that the hydrolysates obtained could be used as an alternative ingredient for the development of new functional foods.