Traditional dairy products can supply beneficial microorganisms able to survive in the gastrointestinal tract

Little is known about the role of traditional dairy products in naturally supplying beneficial microorganisms able to survive in the human gastrointestinal tract (GIT). To investigate this aspect, a fresh artisanal Pasta Filata cheese was administered daily to 18 healthy children, 3–6 years of age, for seven days. Counts and type of lactic acid bacteria (LAB) and propionic acid bacteria (PAB) were carried out on the cheese and children's faeces before and after cheese consumption. In most cases, statistically significant increases of presumptive LAB were observed after seven days from suspension compared to values before and at the end of consumption. Based on repetitive element palindromic PCR (rep-PCR) genotyping, six cheese isolates were identical to faecal isolates. Identity was confirmed by sequencing regions of clpP and rpoD genes for LAB and pepN and proW genes for PAB. Among those cheese isolates P. freudenreichii S-1-P, L. plantarum S-2-2 and L. helveticus S-2-6 stimulated the production of high interleukin 10 (IL-10) and low tumor necrosis factor alpha (TNF-α) levels by peripheral blood mononuclear cells (PBMC). Therefore they could exert anti-inflammatory effects in vivo. Results suggested that traditional dairy products should be more efficiently exploited as a natural source of health-promoting microorganisms.