Effect of fucoidan on properties of BSA-stabilized emulsion

Abstract

Fucoidan, a sulfated polysaccharide, was a very important material valued for biological functions including anti-coagulation, anti-aging, immune system support, cellular communication, and detoxification. However, there are only few studies on its physico-chemical properties in food system. The aim of this work was to elucidate the effect of fucoidan on the emulsifying stability and activity of BSA-stabilized oil-in-water emulsions. Oil-in-water emulsion (20 wt% corn oil, 10mM phosphate buffer, pH 7.4) was prepared and pre-mixed at 13,500rpm with an Ultra-turrax T25 homogenizer for 2min. After mixing, ultrasonics with power generation at 20kHz was used for further emulsification. The activity and stability of emulsion formed with the various concentration of BSA and fucoidan and the sonicating time was investigated using by Delsa™ Nano C(Beckman Coulter, Inc.), Turbiscan Lab expert (Formulaction, France) and Spectrophotometer. The emulsion produced with fucoidan concentration of 1% and sonicating time for 2min had the smallest average particle size(203.6nm) and zeta-potential value(-44.2mV). But, its average particle size was not smaller than BSA-stabilized emulsion. We confer that this result suggested that remaining negative charges of fucoidan formed second layer on stern layer, some positive charge of BSA molecules interact with negative charge of sulfate group of fucoidan. Accordingly, repulsion forces induced among particles in emulsion solution resulted in increasing emulsion stability. The turbidity of emulsified solution at 500nm was decreased during five days of storage. But, the fucoidan-BSA emulsion exhibited a higher value of turbidity as compared to the BSA-stabilized emulsion. In conclusion, fucoidan can be used as an emulsifying stabilizer to improve the physico-chemical properties of food colloidal system.