Identification of antioxidant and ACE-inhibitory peptides in fermented milk

The angiotensin-converting enzyme (ACE)-inhibitory activity and antioxidant properties of a commercial fermented milk from Europe were evaluated. This dairy product showed moderate ACE-inhibitory activity and ABTS(center dot+) radical-scavenging capacity. The peptides from most active fractions collected by reverse phase high-performance liquid chromatography (RP-HPLC) were sequenced by RP-HPLC-tandem mass spectrometry. This technique allowed rapid identification of peptides included in the most active fractions, and various potentially active peptides were recognised according to previous studies of structure-activity relationship. Three of the identified sequences had previously been described as potent ACE inhibitors. The structure of some sequences substantiated the presence of peptides with ACE-inhibitory, antioxidant and immunomodulatory activities. (c) 2005 Society of Chemical Industry.