Fucoidan modification for stable melatonin O/W emulsions: Interfacial structure and properties

Area of Science:

• Food Science and Technology
• Materials Science
• Biochemistry

Background:

• Fucoidans (FUCs) are polysaccharides with potential emulsifying properties.
• Modifying fucoidans can enhance their functionality for delivery systems.
• Melatonin is a bioactive compound with limited bioavailability.

Purpose of the Study:

• To investigate the effects of 2-Octen-1-ylsuccinic anhydride (OSA) modification and ultrasound on fucoidan (FUC) structure and emulsification.
• To develop a stable polysaccharide emulsion system for enhanced melatonin delivery.
• To evaluate the impact of the emulsion on melatonin bioaccessibility and release kinetics.

Main Methods:

• Fucoidans were modified using 2-Octen-1-ylsuccinic anhydride (OSA).
• Ultrasound treatment was applied to the modified fucoidan emulsions.
• Interfacial tension, droplet size, and storage stability were measured.
• Melatonin bioaccessibility and free fatty acid (FFA) release were assessed.

Main Results:

• OSA modification and ultrasound improved fucoidan amphiphilicity and reduced interfacial tension.
• 9%-OSA-FUCs emulsions treated with 400 W ultrasound exhibited the smallest droplet size (1.34 ± 0.03 μm).
• The emulsion system significantly enhanced melatonin bioaccessibility (55.32%) and delayed FFA release.

Conclusions:

• Rational modification of fucoidans with OSA and ultrasound creates highly stable emulsions.
• This delivery system effectively protects melatonin from the gastrointestinal environment, improving absorption.
• The findings offer insights for designing functional polysaccharide-based emulsifiers and delivery systems for hydrophobic compounds.