Explore the Interaction between Ellagic Acid and Zein Using Multi-Spectroscopy Analysis and Molecular Docking.

Area of Science:

• Food Science and Technology
• Biochemistry
• Nutritional Science

Background:

• Growing demand for value-added maize products necessitates understanding protein-bioactive molecule interactions.
• Ellagic acid (EA) is a bioactive molecule with potential health benefits.
• Zein, a major maize protein, is a target for nutritional enhancement.

Purpose of the Study:

• To investigate the interaction mechanism between zein and ellagic acid (EA).
• To explore the potential of zein-EA complexes for developing functional maize-based food products.

Main Methods:

• Fluorescence quenching spectroscopy to determine interaction type and binding sites.
• Ultraviolet-visible (UV-Vis) spectroscopy to confirm complex formation.
• Synchronous fluorescence spectroscopy to analyze changes in the microenvironment of tyrosine residues.
• Circular dichroism (CD) spectroscopy to assess alterations in zein's secondary structure.
• Molecular docking simulations to predict binding modes and interactions.

Main Results:

• Zein and EA interaction primarily involves static quenching via hydrophobic interactions, forming zein-EA complexes.
• EA binding decreases the polarity around tyrosine residues in zein, creating a more hydrophobic environment.
• EA significantly alters zein's secondary structure, increasing alpha-helix and beta-sheet content while decreasing random coils.
• Molecular docking reveals five potential binding sites for EA on zein, involving hydrogen bonds and hydrophobic interactions.

Conclusions:

• The study elucidates the molecular interaction mechanism between zein and EA.
• Findings provide a theoretical foundation for utilizing EA as a functional component in value-added maize protein products.
• Understanding these interactions is crucial for enhancing the nutritional and health benefits of maize-based foods.