In this work, the angiotensin-converting enzyme (ACE)-inhibitory and radical-scavenging activities ofthe
-lactoglobulin (
-Lg)-derived peptides WY f(19-20), WYS f(19-21), WYSL f(19-22), WYSLAf(19-23), WYSLAM f(19-24), and WYSLAMA f(19-25) have been determined. The ACE-inhibitoryactivity (IC
50) varied from 38.3 to 90.4
M, with the exception of WYS (>500
M). All
-Lg-derivedpeptides also exhibited radical-scavenging activity (oxygen radical absorbance capacity (ORAC) valuesranged from 4.45 to 7.67
mol Trolox equivalents/
mol of peptide). The presence and position ofamino acids Trp, Tyr, and Met were proposed to be responsible for the antioxidant activity. Theequimolar amino acid mixtures of all the peptides showed ORAC values lower than those of thecorresponding peptides, indicating that the peptidic bond or the structural conformation had a positiveinfluence on this activity. Finally, positive antioxidant effects of WYS, WYSL, and WYLA with ascorbicacid were observed, whereas WY and WYSLAM showed negative effects, both cases for differentmolar ratio mixtures. These results should be taken into account in the development of new foodingredients on the basis of peptides from
-Lg.