Nano lipid Carriers and Polymer Nanocomposites as Effective Nutraceuticals Delivery Vehicles

Abstract

Omega fatty acids-rich oils (e.g., flaxseed oil and fish oil) are attracting increasing interest in the pharmaceutical and food industries due to their versatile health benefits (e.g., improving mental and cardiovascular health, providing anti-inflammatory effects, preventing immune response disorders, and its positive role in early childhood development). However, the challenges facing the incorporation of the omega fatty acids-rich oils into food products are their high susceptibility to oxidative deterioration which decreases shelf-life, produces off-flavors, and negatively affects consumers’ acceptability of developed products as well as their insolubility in aquoeus media that in turn diminishes its bioavailability. Therefore, the overall aim of this thesis was to enhance the oxidative stability and bioavailability of the omega-3 rich oils through two approaches. In the first approach, omega-3 rich oil-in-water nanoemulsions loaded microspheres were prepared via high speed homogenization and ultrasonication followed by microencapsulation with one of the three wall materials namely, sodium alginate (AL), chitosan (CS), and their combination (ALCS). In the second approach, nanocomposite microspheres were prepared through nanoemulsification of the omega-3 rich oils with exfoliated bentonite (montmorillonite) clay followed by microencapsulation with sodium alginate (AL), chitosan (CS), or their combination (ALCS). In the two studies the microspheres were prepared with and without curcumin (Cur) as an effective natural antioxidant to improve the oxidative stability of the omega-3 rich oils. Nanoemulsion properties (e.g., droplet size, particle size, particle size distribution and zeta potential) were studied using dynamic light scattering (DLS). While nanoemulsion microspheres and nanocomposite microspheres were characterized with the aid of FTIR, XRD, TEM, SEM, and AFM techniques. Nanoemulsion and nanocomposite microspheres functional characteristics (e.g., surface oil, microencapsulation efficiency, loading capacity) were also investigated. The oxidative stability of the prepared microspheres as well as their antioxidant activity was carried out using PV determination and DPPH assay.