Edible alginate/chitosan-based nanocomposite microspheres as delivery vehicles of omega-3 rich oils

A new series of alginate/chitosan-based nanocomposite microspheres was developed to achieve the maximum health benefit and to minimize the oxidation of omega-3 rich oils (flaxseed or fish oils). The nanocomposite microspheres incorporate curcumin (Cur) as natural antioxidant, and have been prepared using a three-step procedure (oil-in-water (o/w) emulsification, gelation and microencapsulation). The average particle size of Cur-free and Cur-loaded nanocomposites ranged between 139 and 153 nm. The presence of omega-3 rich oils in core of the formulated microspheres was confirmed by XRD and FTIR. Optical microscopy, stereo microscopy, SEM and AFM showed a spherical shape of the microspheres. Microencapsulation efficiency, oxidative stability, release profile of oils as well as the antioxidant and antibacterial activities were investigated. The results suggested that the microspheres could be applied as effective and safe edible vehicles for hydrophobic nutraceuticals like omega-3 rich oils with broad spectrum antibacterial activity.