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Published on: November 10, 2016
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Low pH affinity screening of peptides: An alternative to time-consuming storage experiments?
Mads Bjørlie1, Laura Pontoppidan1, Betül Yesiltas1
1National Food Institute, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark.
Food Chemistry
|March 21, 2025
Summary
Researchers screened peptides for antioxidant activity in mayonnaise using novel techniques. However, no peptides improved stability, and some were prooxidants, highlighting challenges in predicting food antioxidant efficacy.
Area of Science:
- Food Science
- Analytical Chemistry
- Biochemistry
Background:
- Metal-catalyzed lipid oxidation shortens mayonnaise shelf life.
- Demand for metal-chelating antioxidants is increasing.
- Efficient screening methods for antioxidants are needed.
Purpose of the Study:
- To screen peptides for antioxidant activity in mayonnaise.
- To evaluate Surface Plasmon Resonance (SPR) and Immobilized Metal Affinity Chromatography (IMAC) at low pH for antioxidant screening.
- To assess the efficacy of novel screening techniques compared to traditional storage experiments.
Main Methods:
- Combined SPR and IMAC at low pH for peptide screening.
- Conducted a 28-day mayonnaise storage experiment.
- Analyzed peptide-metal ion affinity for Ni2+ and Fe3+.
Main Results:
- SPR at low pH faced challenges with non-specific binding.
- IMAC revealed significant variations in peptide-metal ion affinity.
- No tested peptides enhanced mayonnaise oxidative stability; some acted as prooxidants.
Conclusions:
- Novel low pH SPR and IMAC techniques show potential but require refinement.
- Predicting antioxidant efficacy in complex food matrices is challenging.
- Further research is needed to improve low pH screening methodologies for food antioxidants.
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