Anti-diabetic and antihypertensive activities of two flaxseed protein hydrolysate fractions revealed following their simultaneous separation by electrodialysis with ultrafiltration membranes

Flaxseed protein hydrolysate has been fractionated by electrodialysis with two ultrafiltration membranes (20 and 50 kDa) stacked in the system for the recovery of two specific cationic peptide fractions (KCl-F1 and KCl-F2). After 360 min of treatment, peptide migration increased as a function of time in KCl compartments. Moreover, the use of two different ultrafiltration membrane allowed concentration of the 300–400 and 400–500 Da molecular weight range peptides in the KCl-F1 and KCl-F2 fractions, respectively, compared to the initial hydrolysate. After mass spectrometry analysis, higher amounts of low molecular weight peptides were recovered in the KCl-F2 compartment while relatively higher molecular weight peptides were more detected in the KCl-F1 compartment. Amino acid analysis showed that His, Lys and Arg were especially concentrated in the KCl compartments. Finally, glucose-transport assay demonstrated that the KCl-F2 fraction increased glucose uptake while oral administration of KCl-F1 and final FPH decreased systolic blood pressure.