Angiotensin‐converting enzyme inhibitory activity of hydrolysates generated from whey protein fortified with salal fruits (Galtheria shallon) by enzymatic treatment with Pronase from Streptomyces griseus

Abstract

Summary Whey proteins mixed with salal fruits extract (0–20% w/w) were hydrolysed with Pronase E from Streptomyces griseus for a period of 8 h. The angiotensin‐converting enzyme (ACE) inhibitory activity of the hydrolysates was highest (IC50: 0.087 mg mL−1) for samples fortified with the highest extract concentration (20%). Peptides (>7 amino acids) with documented ACE inhibitory activity (DAQSAPLRVY, ALPMHIR, DKVGINY, LHLPLPL, YPFPGPI, YPFPGPIPN, VYPFPGPIPN) were identified bv LC‐MS/MS data analysis using a database search approach. Fluorescence spectra of the whey proteins mixed with salal fruits extract indicates fluorescence quenching for α‐lactalbumin. SDS‐PAGE analysis suggests that α‐lactalbumin is less susceptible to proteolysis when the extract is included in the formula. Data indicate that α‐lactalbumin may be interacting with phenolic compounds naturally present in salal fruits. These interactions and the formation of complexes between a‐Lac and phenolic compounds may affect the hydrolysis pattern of whey protein and the release of peptides with ACE‐inhibitory activity.

Identification of ACE I-Inhibitory Peptides Released by the Hydrolysis of Tub Gurnard (Chelidonichthys lucerna) Skin Proteins and the Impact of Their In Silico Gastrointestinal Digestion

“…Byun and Kim [ 18 ] also found similar ACE-inhibitory activity of Alcalase- and Pronase E-derived Alaska Pollock skin protein hydrolysates. The slight differences in the inhibitory capacity of the samples would be attributed to the specific characteristics of the released peptides, including the amino acid sequence, length, charge and hydrophobicity [ 19 ]. These characteristics will depend on both the enzyme used and the DH, which will be higher or lower following the temperature, pH and hydrolysis time used.…”

Interaction of whey protein with polyphenols from salal fruits (Gaultheria shallon) and the effects on protein structure and hydrolysis pattern by Flavourzyme®

“…Particle size (mean spherical equivalent diameter) of control (0%) and 20% SB was determined using static multiple light scattering with a Turbiscan 2000 apparatus (Formulaction, Ramonville St. Agne, France) according to the method by Raikos et al . () with minor modifications. The light source scanned the samples at 5‐min interval from top to bottom and measured the percentage of light transmitted during a 1 h period at 25 °C.…”

“…Bioactive peptides smaller than 3 kDa from different hydrolysates were identified as described by Raikos et al (2019). About 0.2 mL of samples (0% and 20% SB) hydrolysed with Flavourzyme Ò for 4 and 8 h was centrifuged at 12000 r min À1 for 30 min in Amicon Ò Ultra-0.5 centrifugal filter device (3 kDa) (Sigma-Aldrich), and the filtrate (<3 kDa) was collected.…”