A pool of selectedlacticacidbacteria was used to ferment suspensions of ryeflour. Two-dimensional electrophoresis showed that 109 of the 129 ethanol-soluble rye polypeptides were hydrolysed almost totally by lacticacidbacteria. Matrix-assisted laser desorption ionization—time of flight mass spectrometry and reversed-phase high performance liquid chromatography analysis confirmed the hydrolysis of prolamins. After 48 h fermentation, no prolamin polypeptides were recognized by R5-Western analysis. HPLC analysis of glutelin polymers showed a very low bacterial proteolysis but a pH dependent hydrolysis probably due to activation of rye enzymes. Prolamins were extracted from ryeflour and used to produce a peptic–tryptic (PT)-digest for in vitro tests with K 562 (S) sub-clone and Caco-2/TC7 cells of human origin. The PT-digest was also treated with lacticacidbacteria before assay. The Minimal Agglutinating Capacity increased ca. 8-times when K 562 (S) sub-clone cells were exposed to rye PT-digest treated with lacticacidbacteria. Hydrolysis of rye PT-digest by lacticacidbacteria decreased the toxicity of PT-digest itself towards Caco-2/TC7 cells as estimated by cell viability, caspase-3 activity and release of nitric oxide. Rye prolamins and glutelins were extracted from doughs and subjected to PT digestion. Compared to PT-digests from chemically acidified dough, coeliac jejunal biopsies exposed to the PT-digest from the dough fermented by lacticacidbacteria did not show an increase of the infiltration of CD3+ intraepithelial lymphocytes. The same was found for epithelial cell Fas expression. Long-time fermentation of dough by selectedlacticacidbacteria could be considered as a potential tool to decrease the risk of rye contamination of gluten-free products for coeliac patients.
Fermentation by selected sourdough lactic acid bacteria to decrease coeliac intolerance to rye flour / De Angelis, Maria; R., Coda; M., Silano; Minervini, Fabio; Rizzello, Carlo Giuseppe; Di Cagno, Raffaella; O., Vicentini; M., De Vincenzi; Gobbetti, Marco. - 43:(2006), pp. 301-314. [10.1016/j.jcs.2005.12.008]
Fermentation by selected sourdough lactic acid bacteria to decrease coeliac intolerance to rye flour
RIZZELLO, CARLO GIUSEPPE;
2006
Abstract
A pool of selectedlacticacidbacteria was used to ferment suspensions of ryeflour. Two-dimensional electrophoresis showed that 109 of the 129 ethanol-soluble rye polypeptides were hydrolysed almost totally by lacticacidbacteria. Matrix-assisted laser desorption ionization—time of flight mass spectrometry and reversed-phase high performance liquid chromatography analysis confirmed the hydrolysis of prolamins. After 48 h fermentation, no prolamin polypeptides were recognized by R5-Western analysis. HPLC analysis of glutelin polymers showed a very low bacterial proteolysis but a pH dependent hydrolysis probably due to activation of rye enzymes. Prolamins were extracted from ryeflour and used to produce a peptic–tryptic (PT)-digest for in vitro tests with K 562 (S) sub-clone and Caco-2/TC7 cells of human origin. The PT-digest was also treated with lacticacidbacteria before assay. The Minimal Agglutinating Capacity increased ca. 8-times when K 562 (S) sub-clone cells were exposed to rye PT-digest treated with lacticacidbacteria. Hydrolysis of rye PT-digest by lacticacidbacteria decreased the toxicity of PT-digest itself towards Caco-2/TC7 cells as estimated by cell viability, caspase-3 activity and release of nitric oxide. Rye prolamins and glutelins were extracted from doughs and subjected to PT digestion. Compared to PT-digests from chemically acidified dough, coeliac jejunal biopsies exposed to the PT-digest from the dough fermented by lacticacidbacteria did not show an increase of the infiltration of CD3+ intraepithelial lymphocytes. The same was found for epithelial cell Fas expression. Long-time fermentation of dough by selectedlacticacidbacteria could be considered as a potential tool to decrease the risk of rye contamination of gluten-free products for coeliac patients.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
