Amylase/trypsin-inhibitors (ATIs) are putative triggers of non-celiac gluten sensitivity (NCGS), but contents of ATIs in different wheat species were not available. Therefore, the predominant ATIs 0.19+0.53, 0.28, CM2, CM3 and CM16 in eight cultivars each of common wheat, durum wheat, spelt, emmer and einkorn grown under the same environmental conditions were quantitated by targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) and stable isotope dilution assays (SIDA) using specific marker peptides as internal standards. The results were compared to a label-free untargeted LC-MS/MS analysis, in which protein concentrations were determined by intensity based absolute quantitation (iBAQ). Both approaches yielded similar results. Spelt and emmer had higher ATI contents than common wheat, with durum wheat in between. Only three of eight einkorn cultivars contained ATIs in very low concentrations. The distribution of ATI types was characteristic for hexaploid, tetraploid and diploid wheat species and suitable as species-specific fingerprint. The results point to a better tolerability of einkorn for NCGS patients, because of very low total ATI contents. Targeted LC-MS/MS Reveals Similar Contents of α-Amylase/Trypsin-Inhibitors as Putative Triggers of Nonceliac Gluten Sensitivity in All Wheat Species except Einkorn.
Article in Journal of Agricultural and Food Chemistry 66(46) · October 2018. Sabrina Geisslitz, Christina Ludwing, Katharina Scherf (Technische Universität München Munich, Bayern, Germany).