Bioactive peptides released by lactic acid bacteria fermented pistachio beverages

Fruit and vegetable are the raw materials for many popular fermented beverages with potential health benefits. In the present study, a novel pistachio beverage fermented with selected strains of lactic acid bacteria belonging to the species Leuconostoc pseudomesenteroides and Companilactobacillus paralimentarius was produced, and the extent of proteolysis was evaluated. Physico-chemical and microbiological analyses, together with peptidomics and proteomics, were carried out on the beverage after 24 h of fermentation, using both the non-inoculated and chemically acidified beverage as controls. Amino acid sequence of hundreds of peptides mainly released from 2S albumin, 11S and 7S globulin were characterized. The number and frequency of identified peptides were higher in beverage started with Leuconostoc pseudomesenteroides, followed by Companilactobacillus paralimentarius and acidic beverage. These results suggest that, in addition to endogenous proteases active at acidic pH, the proteolytic system of LAB directly participated to peptide degradation to some extent. According to the BIOPEP database, a group of 31 peptides were potentially bioactive, and primarily associated with antioxidative properties, ACE and DPP-IV inhibition. The beverage started with Leuconostoc pseudomesenteroides showed the highest amount and number of bioactive peptides. This study lays the foundations for the design of novel pistachio-fermented beverage with potential health properties.