Novel whey-derived peptides with inhibitory effect against angiotensin-converting enzyme: in vitro effect and stability to gastrointestinal enzymes

Peptides. 2011 May;32(5):1013-9. doi: 10.1016/j.peptides.2011.02.005. Epub 2011 Feb 16.


Whey protein concentrate (WPC) was subjected to enzymatic hydrolysis by proteases from the flowers of Cynara cardunculus, and the resulting angiotensin-converting enzyme (ACE)-inhibitory effect was monitored. The whole WPC hydrolysate exhibited an IC(50) value of 52.9 ± 2.9 μg/mL, whereas the associated peptide fraction with molecular weight below 3 kDa scored 23.6 ± 1.1 μg/mL. The latter fraction was submitted to RP-HPLC, and 6 fractions were resolved that exhibited ACE-inhibitory effects. Among the various peptides found, a total of 14 were identified via sequencing with an ion-trap mass spectrometer. Eleven of these peptides were synthesized de novo--to validate their ACE-inhibitory effect, and also to ascertain their stability when exposed to simulated gastrointestinal digestion. Among them, three novel, highly potent peptides were found, corresponding to α-lactalbumin f(16-26)--with the sequence KGYGGVSLPEW, α-lactalbumin f(97-104) with DKVGINYW, and β-lactoglobulin f(33-42) with DAQSAPLRVY; their IC(50) values were as low as 0.80 ± 0.1, 25.2 ± 1.0 and 13.0 ± 1.0 μg/mL, respectively. None of them remained stable in the presence of gastrointestinal enzymes: they were partially, or even totally hydrolyzed to smaller peptides--yet the observed ACE-inhibitory effects were not severely affected for two of those peptides.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiotensin-Converting Enzyme Inhibitors / chemistry*
  • Angiotensin-Converting Enzyme Inhibitors / pharmacology*
  • Gastrointestinal Tract / enzymology*
  • Milk Proteins / chemistry*
  • Peptides / chemistry*
  • Peptides / pharmacology*
  • Peptidyl-Dipeptidase A / metabolism*
  • Whey Proteins


  • Angiotensin-Converting Enzyme Inhibitors
  • Milk Proteins
  • Peptides
  • Whey Proteins
  • Peptidyl-Dipeptidase A