摘要：The ability of lactic acid bacteria to release bioactive peptides is strain specific and is
dependent on the dairy processing conditions. In the present study, we developed a
starter for fermented milk with increased proteolytic and peptidolytic activity. The
structure and concentration of bioactive peptides are strongly dependent on the strainspecific
proteolytic complex. It could be expected that such peptides would be released
during the process of manufacture of fermented milk. Among the possible bioactivities
of released peptides is the inhibitory effect against angiotensin converting enzyme
(ACE), whose increased activity could lead to an elevation of the blood pressure.
Evaluation of the peptides IPP and VPP with proven ACE-inhibitory activity was
performed by UPLC-MS-MS. The quantification of peptides IPP and VPP was
performed by selected reaction monitoring (SRM) method using certified standards.
In this study, we developed a starter containing L. helveticus, L. bulgaricus, and S.
thermophilus strains. The strains L. helveticus A1 and L. bulgaricus J24 possess strong
proteolytic complex which lead to increased content of ACE inhibitory peptides. After
a pilot production of fermented yoghurt with the developed starter, the concentration
of IPP and VPP was assessed by UPLC-MS-MS. The inclusion of the highly
proteolytic strain L. helveticus A1 in the starter culture leads to increased production
of bioactive peptides in the fermented milk.
