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Lysozyme-phenolics bioconjugates with antioxidant and antibacterial bifunctionalities: Structural basis underlying
Hui Li1, Yanxiong Pan2, Chun Li1
1Department of Plant Sciences, North Dakota State University, Fargo, ND, United States.
Food Chemistry
|December 3, 2022
Summary
Electron Paramagnetic Resonance (EPR) spectroscopy reveals how protein-phenolic conjugation affects antioxidant and antibacterial properties. Rosmarinic acid enhanced antioxidant capacity but reduced lysozyme
Area of Science:
- Biochemistry
- Spectroscopy
- Materials Science
Background:
- Protein-phenolic interactions are crucial for developing functional biomaterials.
- Understanding structure-activity relationships is key for optimizing dual functionalities like antioxidant and antibacterial properties.
Purpose of the Study:
- To investigate the relationship between protein-phenolic conjugation and the resulting antioxidant and antibacterial functionalities.
- To elucidate the structural basis underlying these dual functionalities using Electron Paramagnetic Resonance (EPR) spectroscopy.
- To compare the effects of conjugating lysozyme (Lys) with rosmarinic acid (RA) versus gentisic acid (GA).
Main Methods:
- Utilized Electron Paramagnetic Resonance (EPR) spectroscopy to study protein-phenolic conjugation.
- Employed site-directed spin labeling (SDSL)-EPR to explore structural changes, reactivity, and selectivity.
- Conjugated lysozyme with rosmarinic acid and gentisic acid.
Main Results:
- Lysozyme-rosmarinic acid (Lys-RA) showed significantly enhanced antioxidant stoichiometry compared to native lysozyme and lysozyme-gentisic acid (Lys-GA).
- Rosmarinic acid conjugation led to a decrease in both enzymatic and antibacterial activities of lysozyme.
- Significant structural and surface property changes in lysozyme were observed upon rosmarinic acid conjugation.
Conclusions:
- Polyphenol conjugation significantly alters protein structure and function, impacting dual antioxidant and antibacterial activities.
- EPR spectroscopy, particularly SDSL-EPR, provides insights into the dynamic structural basis of reactivity and selectivity in protein-phenolic interactions.
- The choice of phenolic acid influences the balance between enhanced antioxidant capacity and potential mitigation of other functionalities.
Keywords:
Antibacterial activityAntioxidant activityPolyphenol reactivity and selectivityProtein–polyphenol conjugatesStructure-functionalities relationshipMore Related Videos
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