The addition of probiotic promotes the release of ACE-I peptide of Cheddar cheese: Peptide profile and molecular docking

The use of probiotics to promote the release of bioactive peptides during Cheddar cheese ripening was investigated. The proteolytic and angiotensin-converting enzyme inhibitory (ACE-I) activities and ACE-I peptide profile of Cheddar cheese with different probiotics were analysed and compared. Molecular docking was used to analyse the binding site of peptide to ACE molecule. Compared with other cheeses, ACE-I activity of Lactobacillus helveticus cheese was the highest (79.71%), and the degree of proteolysis was higher and the molecular mass was lower. Most of the peptides were less than 1.6 kDa. In addition, 43.31–51.59% of the peptides in cheese originated from β-casein, mainly from the degradation of starter and probiotics. SKVLPQ and YQEPVLGP, which were uniquely identified in L. helveticus cheese, could interact with the S1 and S2 active pocket of ACE, respectively. Especially, YQEPVLGP could bind to ACE at multiple sites and was an efficient ACE inhibitory peptide.