Main content area

Selective separation and concentration of antihypertensive peptides from rapeseed protein hydrolysate by electrodialysis with ultrafiltration membranes

He, Rong, Girgih, Abraham T., Rozoy, Elodie, Bazinet, Laurent, Ju, Xing-Rong, Aluko, Rotimi E.
Food chemistry 2016 v.197 pp. 1008-1014
amino acids, animal disease models, body weight, digestion, dose response, electrodialysis, hypertension, inhibitory concentration 50, oral administration, peptides, peptidyl-dipeptidase A, protein hydrolysates, protein isolates, rapeseed protein, rats, renin, subtilisin, systolic blood pressure, ultrafiltration
Rapeseed protein isolate was subjected to alcalase digestion to obtain a protein hydrolysate that was separated into peptide fractions using electrodialysis with ultrafiltration membrane (EDUF) technology. The EDUF process (6h duration) led to isolation of three peptide fractions: anionic (recovered in KCl-1 compartment), cationic (recovered in KCl-2 compartment), and those that remained in the feed compartment, which was labeled final rapeseed protein hydrolysate (FRPH). As expected the KCl-1 peptides were enriched in negatively-charged (43.57%) while KCl-2 contained high contents of positively-charged (28.35%) amino acids. All the samples inhibited angiotensin converting enzyme (ACE) and renin activities in dose-dependent manner with original rapeseed protein hydrolysate having the least ACE-inhibitory IC50 value of 0.0932±0.0037mg/mL while FRPH and KCl-2 had least renin-inhibitory IC50 values of 0.47±0.05 and 0.55±0.06mg/mL, respectively. Six hours after oral administration (100mg/kg body weight) to spontaneously hypertensive rats, the FRPH produced the maximum systolic blood pressure reduction of −51mmHg.