Xanthan gum-stabilized docosahexaenoic acid loaded nanoemulgel: A stable nutraceutical delivery system with enhanced bioavailability

Docosahexaenoic acid (DHA) is an omega-3 fatty acid beneficial for brain development and cardiovascular health. DHA has poor aqueous solubility and is highly susceptible to oxidation, limiting its bioavailability. To address these challenges, in the present investigation, nanoemulsion was prepared using DHA-enriched edible algal oil and tween 80 as an emulsifier (1 %) initially. Then, the prepared DHA nanoemulsion was subsequently incorporated into xanthan gum gel (1.5 % w/v) to develop nanoemulgel. DHA nanoemulsion incorporated in the gel matrix achieved higher electrostatic stability of -69.17 ± 0.36 mV and a droplet size of 57.4 ± 0.52 nm, with maximum stability achieved at pH 7. The encapsulation efficiency of DHA in nanoemulgel found using GC-FID was 98.8 %. At the end of storage (120 days), the concentration of DHA in nanoemulgel was 3.4 g/100 g. The biocompatibility of nanoemulgel was confirmed by an in vitro cytotoxicity assessment using HepG2 cells and a hemolysis assessment. The nanoemulgel had a higher release of DHA (90 %) in in vitro gastric and intestinal digestion. In addition to that, in vivo pharmacodynamic evaluations in male C57BL mice were conducted to assess the cognitive enhancement. In comparison to the control group (0.39 g/100 g), the brain tissue of mice fed with DHA nanoemulgel showed a greater increase in DHA content (0.7 g/100 g) with an increased glial cell population. In short, an innovative strategy of combining DHA nanoemulsion with a gel matrix to develop nanoemulgel increased the bioavailability and stability of DHA, showing its potential as a promising nano delivery system for nutraceuticals.