Revealing the structure and functional properties of cationic phytoglycogen

Area of Science:

• Food Science
• Polymer Chemistry
• Biomaterials

Background:

• Phytoglycogen (PG) is a natural polysaccharide with potential in food applications.
• Cationization can modify PG properties for enhanced functionality.
• Understanding structure-property relationships is crucial for targeted applications.

Purpose of the Study:

• To investigate the structure-property relationships of cationized phytoglycogen (PG) modified with 2,3-epoxypropyl trimethylammonium chloride (GTAC).
• To assess the impact of varying degrees of substitution (DS) on PG derivative properties.
• To provide insights for optimizing PG derivatives in functional food applications.

Main Methods:

• ¹³C nuclear magnetic resonance (NMR) for structural characterization.
• Enzymatic hydrolysis coupled with tandem mass spectrometry (MS) for cationic group localization.
• Rheology, thermogravimetric analysis (TGA), and interfacial stability analysis for property assessment.
• Density functional theory (DFT) simulations for reaction pathway analysis.

Main Results:

• ¹³C NMR confirmed preferential grafting of GTAC at the C-2 position of glucose units.
• MS revealed cationic group clustering near branch points and non-reducing ends.
• Properties like viscosity, elasticity, thermal stability, and interfacial tension modulation varied with DS.
• DFT identified six reaction pathways, with Ia showing high energy and reactivity.

Conclusions:

• The degree of substitution (DS) significantly influences the properties of cationized PG derivatives.
• Precise modification of PG with GTAC can yield tailored properties for specific food applications.
• Optimized PG derivatives show promise for stabilized emulsions, fat mimics, and controlled release systems.