Separation and identification of ACE inhibitory peptides from defatted walnut meal

• DOI: 10.1007/s00217-020-03553-5
• Publication Date: 2020-07-23T18:04:40Z
• Authors: Yonghao Chen; Jun Li; Ningguang Dong; Yunqi Zhang; Xiaodan Lu; Yanbin Hao; Jianxun Qi
• Keywords: Ultrafiltration (renal); IC50

The peptide obtained from walnut protein enzymatic hydrolysate had high ACE inhibitory activity. Through centrifugation, ultrafiltration, gel chromatography and high performance liquid chromatography (HPLC), the walnut oligo-peptide, which was denoted as P4-c with high ACE inhibitory activity was obtained. Three novel ACE inhibitory peptides, GVVPHN, EHSLDPLK and KTLLNFGPN, were identified from P4-c by high-resolution ion mobility mass spectrometry (IM-MS). The three novel ACE inhibitory peptides possessed good ACE inhibitory activity and the fraction GVVPHN had high ACE inhibitory activity with 27.3 µmol L−1 of IC50. The molar percentage of hydrophobic amino acids in the peptide GVVPHN was 50% while the hydrophobic amino acid contents of EHSLDPLK and KTLLNFGPN were 37.5% and 44.4%, respectively, which indicates ACE inhibitory activities were hydrophobicity of amino acid-dependent.