Ruolo delle peptidasi dei LAB nell'idrolisi delle gliadine antigeniche e di peptidi derivanti da 33-mer

Celiac disease (CD) is one of the most common food intolerance. The only effective treatment for CD is a strict adherence to a gluten free diet throughout the patient’s lifetime. There is, therefore, an urgent need to develop safe and effective therapeutic alternatives, to develop high-quality glutenfree products and to investigate the potential of the bread making biotechnology following ancient protocols which include longtime fermentation by selected sourdough lactic acid bacteria. For this aim several strains belonging to differentLactobacillusspecies isolated from Sardinia sourdough, were characterized for their ability to produce specialized peptidases capable of hydrolyzing Glu- e Pro-rich peptides, including a gliadin-like fragment derived from the 33-mer peptide, which is the most potent inducer of gut-derived human T-cell lines inCDpatients. We showed here that after 24 hour of fermentation, wheat gliadins and low-molecular mass, alcohol-soluble polypeptides, were almost completely hydrolyzed in sourdoughs made from wheat flours and separately inoculated with all the LAB strains tested. Moreover, cell-free extracts (CFE) recovered from all of the LAB strains tested were also able to completely hydrolyse antigenic gliadin-like fragments derived from the 33-mer peptide, which is the most important inCD.