The microbiota of Kalathaki and Melichloro Greek artisanal cheeses comprises functional lactic acid bacteria

Artisanal cheeses, in particular those prepared from raw milk, are the most commonly used ecosystems to mine microorganisms with both technological and human-health related potential. In the present study, the microbiota of two Greek artisanal cheeses, the PDO Kalathaki and the non-PDO Melichloro, was explored via classical microbiological analysis. Lactic acid bacteria isolated mainly belonged to the genus Enterococcus (66%) and to a lesser degree to Pediococcus (15%), Leuconostoc (8%), Lactobacillus (6%) and Lactococcus (5%). From the 112 initial isolates, 32 were selected and studied for their probiotic potential, i.e. safety traits, survival under gastrointestinal tract conditions, antimicrobial activity, adhesion, angiotensin I-converting enzyme inhibitory activity and immunomodulation of human monocytes. Two isolates, namely Lactobacillus brevis ACA-DC 1705 and Leuconostoc mesenteroides ACA-DC 1738, exhibited the most promising probiotic potential due to strong angiotensin I-converting enzyme inhibitory activity and anti-inflammatory modulation of immune cells, respectively, and, thus they could be used as adjuncts in novel functional products.