Purification and characterization of angiotensin I-converting enzyme inhibitory peptides of small red bean (Phaseolus vulgaris) hydrolysates.
Joyce Boye , Xin, R., B. K. Simpson and O. P. Shiv
Nom de la revue: Journal of Functional Foods 5(3): 1116-1124.
Angiotensin I-converting enzyme (ACE) inhibitory activity was investigated for small red bean (Phaseolus vulgaris) protein hydrolysate produced by sequential digestion of Alcalase, papain followed by in vitro gastrointestinal simulation. The hydrolysate had ACE inhibitory activity with IC50
of 67.2 +or- 1.8 mug protein/mL. Peptides responsible for potent ACE inhibitory activity were isolated by a three-step purification process, including ultrafiltration, gel filtration and preparative reverse phase high performance chromatography (RP-HPLC). The fraction obtained after RP-HPLC fractionation with the highest activity yielded an IC50
of 19.3 +or- 1.4 mug protein/mL. Enzymatic kinetic studies using this fraction demonstrated competitive inhibition with Ki
of 11.6 +or- 1.7 mug protein/mL. Mass spectrometric characterization identified for the first time the octapeptide PVNNPQIH which demonstrated an IC50
value of 206.7 +or- 3.9 muM. The results expand the knowledge base of ACE inhibitory properties of small red bean protein hydrolysate and should be useful in further identification of specific ACE inhibitory peptides in beans.