TY  - JOUR
A1  - Uhr, Linda
A1  - Buchholz, Tina
A1  - Homann, Thomas
A1  - Huschek, Gerd
A1  - Rawel, Harshadrai Manilal
T1  - Targeted proteomics-based analysis of technical enzymes from fungal origin in baked products
T2  - Journal of cereal science
N2  - The application of technical enzymes is a potential tool in modulating the dough and baking quality of cereal products. No endogenous amylases (alpha- and beta-forms) are present in mature wheat grains; they may be synthesized or activated during germination. Hence, microbial alpha-amylases are added to the dough, being resistant to the endogenous alpha-amylase/trypsin inhibitors. Here, we report on the initial identification of two technical enzymes from a commercial sample based on an in-gel tryptic digestion coupled with MALDI-MS analysis. The primary component of the protein fraction with 51.3 kDa was alpha-amylase from Aspergillus species. A second major protein with 24.8 kDa was identified as endo-1,4-xylanase from Thermomyces lanuginosus. In the following experimental work up, a targeted proteomics approach utilizing the combination of specific proteolytic digestion of the added amylase and xylanase in wheat flour, dough or baked products, solid phase extraction of released peptides and their detection using LC-MS/MS was optimized. The targeted (MRM) MS/MS peptide signals showed that the peptide "ALSSALHER" (MW = 983) originating from amylase and "GWNPGLNAR" (MW = 983) from xylanase can be used to identify the corresponding technical enzymes added. Consequently, locally available baked products were tested and found to contain these enzymes as supplementary ingredients. (C) 2014 Elsevier Ltd. All rights reserved.
KW  - Technical enzymes
KW  - Amylase
KW  - Xylanase
KW  - Mass spectrometry
Y1  - 2014
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/37590
SN  - 0733-5210
SN  - 1095-9963
VL  - 60
IS  - 2
SP  - 440
EP  - 447
PB  - Elsevier
CY  - London
ER  -