Preparation of an ACE-inhibitory peptide from Perinereis aibuhitensis protein

Abstract

ABSTRACTThe peptides with angiotensin-I converting enzyme (ACE)-inhibition activity were prepared from Perinereis aibuhitensis protein (PAP) by hydrolysis with neutral protease, in which the ACE-inhibition rate of peptides derived from PAP was monitored. The hydrolysis conditions were optimised as follows: reaction time 5 h, temperature 50 °C, pH 7 and enzyme amount 0.5%. Under the optimum hydrolysis conditions, the ACE-inhibition rate of peptides of PAP reached up to 83.61%. The hydrolysates were fractionated into two molecular-weight ranges (below and above 10 kDa) by ultrafiltration. The below-10-kDa fraction with higher ACE-inhibitory was subsequently purified by Sephadex G-15 gel filtration chromatography. The structure of the active peptide was identified as Gly-Ala-Phe by high performance liquid chromatography (HPLC) coupled with quadrupole (Q) time-of-flight (TOF) mass spectrometry (HPLC-Q-TOF-MS). Thus, the peptide prepared from PAP by hydrolysis with neutral protease could be a beneficial ingredient of nutraceuticals and pharmaceuticals against hypertension.