Utilization of bovine blood plasma proteins for the production of angiotensin I converting enzyme inhibitory peptides

Hydrolysates of whole bovine plasma and its separated proteins? albumin and globulins, which inhibit the angiotensin I converting enzyme (ACE) were pr epared by enzymic hydrolysis with several proteases available for industria l use. Alcalase produced ACE inhibitory peptides from plasma proteins most efficiently and the Alcalase hydrolysate of albumin showed the most high ac tivity (IC50 = 0.56 mg/ml). Sequential ultrafiltration of the hydrolysate w ith MW cut-off 10 000, 3000 and 1000 resulted in increased activity of each filtrate up to IC50 of 0.12 mg/ml. Sephadex G-25 gel chromatography of the hydrolysate eluted a peptide fraction below MW 1000 of the most potent act ivity (IC50 = 0.09 mg/ml). The hydrolysate was compared with the tryptic hy drolysate of casein considering the practical production of a functional fo od material in industry. The former was found to be mole advantageous to se parate the purified peptide fraction by industrial processes. (C) 2000 Else vier Science Ltd. All rights reserved.