Unsaturated guluronate oligosaccharide used as a stabilizer of oil-in-water nanoemulsions loaded with bioactive nutrients

Abstract

Unsaturated guluronate oligosaccharide (GOS) is generated via alginate-derived polyguluronate (PG) degradation by alginate lyase, followed by formation of a double bond between C-4 and C-5 at the nonreducing end. In this study, GOS was first used as a stabilizer to fabricate O/W nanoemulsions loaded with resveratrol (GOS-RES). Our results revealed that both the GOS-RES and normal O/W resveratrol nanoemulsions (water-RES) showed small droplet sizes and narrow size distributions under certain experimental conditions. However, the particle size and stability of the GOS-RES were slightly greater than those of the water-RES in acidic and neutral environments and at high temperatures. Furthermore, the GOS-RES exhibited a better sustained release effect for resveratrol than the water-RES. Moreover, the GOS-RES showed a significant superoxide radical scavenging effect. All these results demonstrated that GOS has good prospects for preparing nanoemulsions to encapsulate hydrophobic nutrients, which could be applied as food-grade components in beverages and other foods.

Keywords

• Unsaturated guluronate oligosaccharide
• O/W nanoemulsion
• Resveratrol
• Sustained release
• Antioxidant activity