Angiotensin I-converting (ACE)-inhibitory and anti-inflammatory properties of commercially available Greek yoghurt made from bovine or ovine milk: A comparative study

The objective of this study was to compare the presence of peptides with angiotensin I-converting (ACE)-inhibitory and immunomodulatory activities in commercial Greek yoghurt made from bovine or ovine milk. Water soluble extracts (WSE) in yoghurts made from ovine milk exhibited higher ACE-inhibitory activity than their bovine counterparts. Similarly, ovine yoghurt WSE inhibited more effectively the expression of two pro-inflammatory genes (inducible NO synthase and cyclooxygenase-2) by ovine monocytes. Following gel filtration of WSE by Sephadex G25, one fraction exhibited only ACE-inhibitory activity, two only immune inhibitory while one possessed both activities. Thus, selected peptidic fractions mimicked the original effects observed in WSE prior to fractionation.