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Updated: Jan 9, 2026
10:07
Identification of Post-translational Modifications of Plant Protein Complexes
Published on: February 22, 2014
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Molecular Interplay Between Plant Proteins and Polyphenols: pH as a Switch for Structural and Functional Assembly
Havva Aktaş1,2, Arkadiusz Szpicer1, Barbara Strojny-Cieślak3
1Department of Technique and Food Development, Institute of Human Nutrition Sciences, Warsaw University of Life Sciences (WULS-SGGW), 02-776 Warsaw, Poland.
Foods (Basel, Switzerland)
|December 11, 2025
Summary
This study reveals how pH affects plant protein-polyphenol interactions, influencing antioxidant activity and food formulation stability. Alkaline conditions enhance binding but cause aggregation, while specific proteins offer unique benefits across different pH levels.
Area of Science:
- Food Science
- Biochemistry
- Materials Science
Background:
- Plant proteins and polyphenols are key natural food ingredients.
- Understanding their interactions is crucial for food functionality.
- pH significantly influences these complex interactions.
Purpose of the Study:
- To investigate pH-dependent binding mechanisms between plant proteins and polyphenols.
- To analyze structural transformations and functional properties of protein-polyphenol complexes.
- To explore the potential of underutilized proteins like mustard protein concentrate (MP), primrose protein meal (PP), and sunflower meal protein isolate (SMP) with red cabbage polyphenols (RC).
Main Methods:
- Spectroscopic techniques (e.g., UV-Vis, fluorescence) to study binding and structure.
- Microscopic techniques (e.g., CLSM) to visualize complex formation and emulsion structure.
- Assays for antioxidant activity, solubility, emulsification, and foaming properties.
- pH manipulation (acidic, neutral, alkaline) to observe effects.
Main Results:
- Alkaline pH (7-9) enhanced anthocyanin binding in PP and SMP via hydrogen bonding and hydrophobic interactions.
- Increased binding at alkaline pH led to protein unfolding and aggregation, impacting solubility.
- Primrose protein meal (PP) showed highest antioxidant activity at pH 9, while mustard protein concentrate (MP) maintained anthocyanin stability at acidic pH.
- Emulsification and foaming varied: PP excelled at acidic pH, MP at alkaline pH, and SMP performed consistently across all pH.
- Confocal Laser Scanning Microscopy (CLSM) confirmed SMP-based emulsions exhibited superior structural stability.
Conclusions:
- pH is a critical factor governing the assembly, stability, and functionality of plant protein-polyphenol complexes.
- Specific protein-polyphenol combinations and pH conditions can be optimized for desired functionalities like antioxidant activity and emulsion stability.
- Findings support the rational design of advanced plant-based food formulations using underutilized protein sources.
Keywords:
anthocyaninsantioxidant functionalitypH effectsplant proteinsprotein–polyphenol complexesstructural transitionsMore Related Videos
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