European Food Research and Technology

, 230:89

Detection of an angiotensin converting enzyme inhibitory peptide from peanut protein isolate and peanut polypeptides by western blot and dot blot hybridization

Original Paper

DOI: 10.1007/s00217-009-1136-7

Cite this article as:
Liu, Ln., Zhang, Sh. & He, Dp. Eur Food Res Technol (2009) 230: 89. doi:10.1007/s00217-009-1136-7


The peptide P7, with an amino acid sequence of Cys-Val-Thr-Pro-Ala-Leu-Arg, inhibits angiotensin I-converting enzyme (ACE). In this paper, P7 was identified in peanut protein isolate (PPI) and peanut polypeptides (PPs) with a new method. The P7 peptide was synthesized and used in the preparation of an antiserum. Using the antiserum, P7 was specifically identified in PPI by western blot, and its level in PPI and PPs was assayed by dot blot hybridization. The results showed that two bands of P7 expression with molecular weight 18–25 and 25–35 kDa were seen in PPI by glucan gel chromatography. The positive reaction rate of P7 in PPs was higher than in PPI, consistent with the measured ACE inhibitory activity. The rate of P7 in sample no. 3 reached 39.29% of the positive control, using a dose of 20 μg/mL. This sample had an ACE inhibitory activity of 89.73%. Therefore, western blot and dot blot hybridization with prepared antibody against synthetic peptide was a very sensitive detection method for peptide.


Peanut protein isolatePeanut polypeptidesAngiotensin I-converting enzyme inhibitory peptideWestern blotDot blot hybridization



Peanut protein isolate


Peanut polypeptides


Angiotensin I-converting enzyme


Synthetic peptide with an amino acid sequence of Cys-Val-Thr-Pro-Ala-Leu-Arg

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  1. 1.College of Food Science and TechnologyHuazhong Agricultural UniversityWuhanChina
  2. 2.College of Food Science and EngineeringWuhan Polytechnic UniversityWuhanChina