Abstract:This experiment adopted six kinds of commercial protease Alcalase 2.4L, trypsin, pepsin,
flavourzyme, nuetrase AS1398 and papain to hydrolyze porcine hemoglobin in optimum reaction
conditions for 12 hours respectively, and the hydrolysates were assayed for the inhibitory activity of
angiotensin-I converting enzyme (ACE) and the protein hydrolysis degree. The results showed that the
ACE inhibitory activity of pepsin-derived hydrolysates was highest in all the proteases. The condition
of enzymatic hydrolysis of pepsin was: substrate concentration was 5%, enzyme/substrate ratio was 3%,
temperature was 37℃, pH 2.0, and in the 4th hour the inhibitory activity of ACE reached 81.10% and
the degree of hydrolysis was 6.64%.