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Quantitative FRET Förster Resonance Energy Transfer Analysis for SENP1 Protease Kinetics Determination
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Pyro-Thermolysis Pattern Analysis of Selenopeptide in Selenium-Enriched Rice Based on Two-Dimensional Dietary
Xin Wang1, Wei Jia1, Rong Zhang1
1School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China.
Journal of Agricultural and Food Chemistry
|January 22, 2025
Summary
This study identifies selenopeptides in selenium-enriched rice, like L-selenomethionyl-alanyl-lysine (L{Se-Met}AK), and analyzes their thermal degradation. LMAK is proposed as a quality control marker for retaining these valuable dietary selenium supplements.
Area of Science:
- Food Science
- Biochemistry
- Analytical Chemistry
Background:
- Selenopeptides are promising dietary selenium supplements.
- Rice is an underutilized source of selenopeptides.
- Selenium enrichment in rice can enhance its nutritional value.
Purpose of the Study:
- To identify and characterize selenopeptides in selenium-enriched rice protein hydrolysates.
- To investigate the thermal degradation kinetics of a specific selenopeptide, L{Se-Met}AK.
- To identify potential quality control markers for selenopeptide retention during thermal processing.
Main Methods:
- Selenopeptidomics analysis using full MS-dd-MS2 acquisition.
- Identification of selenomethionine (SeMet) incorporation into rice proteins (Oryzain alpha chain).
- Thermal degradation studies at 100, 110, and 120 °C, analyzing activation energy (Ea) and pyrolysis products.
Main Results:
- Identified L{Se-Met}AK and other selenopeptides in selenium-enriched rice hydrolysates.
- Established thermal degradation rate equations for L{Se-Met}AK.
- Identified pyrolysis products including L{Se-Met}A, LMA, LMAK, K1, and K2, with LMAK exhibiting lower activation energy (88.20 kJ/mol).
Conclusions:
- L{Se-Met}AK is formed by SeMet replacing Met in rice proteins.
- Thermal processing leads to selenopeptide cleavage, impacting retention.
- LMAK can serve as a quality control marker for efficient selenopeptide retention during pyrolysis.
Keywords:
UHPLC-Q-Orbitrap HRMSpyrolytic reactionseleniumselenopeptide degradationselenopeptide-L{Se-Met}AKMore Related Videos
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