Angiotensin-Converting Enzyme Inhibition In Vitro by Protein Hydrolysates and Peptide Fractions from Mojarra of Nile Tilapia (Oreochromis niloticus) Skeleton.

Mojarra of Nile tilapia (Oreochromis niloticus) skeleton was used as protein source for the preparation of protein hydrolysates and peptide fractions with angiotensin-converting enzyme (ACE) inhibitory activity. The flour presented a content of 34.92% protein and a brightness (luminosity, L*) of 82.29. Protein hydrolysates were obtained from the protein-rich flour with the enzymes Flavourzyme® and Alcalase® reaching degree of hydrolysis (%DH) of 52% and 67% at 100 min of reaction, respectively. Both hydrolysates showed low-molecular-weight (MW) peptides estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The hydrolysates obtained with Flavourzyme at 60 min and at 80 min with Alcalase showed greater ACE inhibitory activity with IC50 values of 0.238 and 0.344 mg/mL, respectively. The peptide fraction A (MW >10 kDa) with Flavourzyme and fraction B (MW = 10-5 kDa) with Alcalase obtained by ultrafiltration of hydrolysates with higher DH presented IC50 of 0.728 and 0.354 mg/mL, respectively, whereas peptide fraction C (MW = 5-3 kDa) with both enzymes hydrolysates with greater ACE inhibitory activity showed IC50 values of 0.470 and 0.634 mg/mL. The components obtained in this study could be used as functional ingredients in the design and development of functional foods.

Encapsulation of Phaseolus lunatus Protein Hydrolysate with Angiotensin-Converting Enzyme Inhibitory Activity.

The objective of recent research has been to seek alternative therapeutic treatments; for this reason, the use of protein hydrolysates from diverse sources has been studied. A way to guarantee that these treatments reach the site of action is through protection with covers, such as microcapsules. Therefore, proteins from the legume Phaseolus lunatus were hydrolyzed and encapsulated with a blend of Delonix regia carboxymethylated gum/sodium alginate (50 : 50 w/w). Hydrolysis release conditions in a simulated gastrointestinal system were obtained using CaCl2 concentrations as the main factor, indicating that lower CaCl2 concentrations lead to an increased hydrolysis release. Beads obtained with 1.0 mM of CaCl2 exhibited a better hydrolysate release rate under intestinal simulated conditions and the proteins maintained an IC50 of 2.9 mg/mL. Capsules obtained with the blend of Delonix regia carboxymethylated gum/sodium alginate would be used for the controlled delivery of hydrolysates with potential use as nutraceutical or therapeutic agents.