Feta cheese: A pool of Non-Starter Lactic Acid Bacteria (NSLAB) with anti-hypertensive potential

In the present work, we examined the angiotensin-I-converting enzyme-inhibitory (ACE-I) activity of the water soluble extracts of four long-ripened Feta cheese samples. High activity (>87 %) was determined for all of them. Additionally, we fingerprinted the non-starter lactic acid bacteria (NSLAB) isolated from the cheese samples. All NSLAB isolates were screened for their proteolytic activity and the most proteolytic ones were further evaluated for their ACE-I activity as well as ability to produce γ-aminobutyric acid (GABA). The NSLAB isolates comprised 130 lactobacilli and 24 enterococci, with the dominant species being Levilactobacillus brevis , Lactiplantibacillus plantarum , Lacticaseibacillus paracasei and Enterococcus faecium . Among them, 40 selected isolates exhibited high proteolytic activity, with 13 lactobacilli and two enterococci exhibiting strong ACE-I activity (>50 %), and six lactobacilli producing GABA. Thus, the hypertension risk associated with over-consumption of Feta cheese because of its high sodium content may be compensated by the anti-hypertensive traits of NSLAB microbiota members, which are active during the long cheese ripening time.