Title : Nanoemulsions as a strategy to enhance gastrointestinal bioavailability and bioactivity of lipid based nutraceuticals
Abstract:
Water-immiscible lipophilic bioactive compounds can be efficiently dispersed as colloidal droplets within an aqueous matrix in oil-in-water emulsions. This property has drawn considerable attention to nanoemulsions as promising nanodelivery systems, particularly for enhancing the oral bioavailability of lipophilic bioactives by improving their solubilization in the aqueous intestinal environment. Encapsulation using lipid-based nanoformulations is therefore a potent strategy for protecting nutraceuticals and improving their stability and absorption. In our laboratory, multiple nanoformulation strategies employing diverse methods and materials were developed and evaluated for bioavailability using in vitro, in situ, and in vivo models. Nanoemulsions were bioengineered using fish oil (rich in EPA and DHA), bitter gourd oil (rich in conjugated linolenic acid), and sesame oil (rich in sesame lignans). A combination of ascorbyl palmitate, a lipid-soluble vitamin C derivative, phospholipids, protein hydrolysates, natural food emulsifiers, along with Tween 20 and Span 80, was employed. Physicochemical properties and stability were assessed using standard analytical methodologies.
In vitro digestion studies were conducted using simulated gastrointestinal fluids, while absorption characteristics were evaluated using the in situ everted sac model. An in vivo intestinal perfusion model was employed to assess bioavailability and bioactivity of the nanoformulations. Colloidal nanoemulsions were further fabricated using sesame oil and food-grade emulsifiers through a low-energy approach. Real-time cellular uptake and metabolic fate were studied using an ex vivo peripheral blood mononuclear cell. Additionally, the in vivo anti-inflammatory and antioxidant efficacy of the nanoemulsions were demonstrated in appropriate animal models. Overall, these innovative nanoformulations exhibit significant potential for enhancing bioavailability and bioactivity of lipid-based nutraceuticals, highlighting their promising translational and clinical applications.
