Nanoencapsulation of quinoa oil enhanced the antioxidant potential and inhibited digestive enzymes

Quinoa oil is rich in unsaturated fatty acids and vitamin E, but its instability limits its application in food, pharmaceutical, and cosmetic products. Nanoencapsulation emerges as a promising strategy to promote water dispersibility, preserve and enhance functional properties, and increase the bioavailability of bioactive compounds. This study encapsulated quinoa oil through O/W emulsification, using porcine gelatin (OG) and isolated whey protein (OWG) as encapsulating agents. The particles were characterized by different physical and chemical methods and evaluated in vitro for cytotoxicity using Chinese hamster ovary (CHO) cells, human hepatocarcinoma cells (HepG2) and epithelial cells, and bioactive potential through the determination of Total Antioxidant Capacity (CAT) (acidic and neutral media) and iron chelation, and inhibition of digestive enzymes (α-amylase and amyloglucosidase). OG and OWG particles presented smooth surfaces, with an average size between 161 ± 7 and 264 ± 6 nm, with a polydispersity index of 0.11 ± 0.03 and 0.130 ± 0.04, encapsulation efficiency of 74 ± 1.47 % and 83 ± 2.92 %, and water dispersibility >70 %, respectively. Free and nanoencapsulated quinoa oil did not show cytotoxic effects (cell viability >70 %). Nanoencapsulation promoted the enhancement of the antioxidant activity of quinoa oil in the range of 50-63 % in a neutral medium and 96-153 % in an acidic medium than free oil (p < 0.05). OG and OWG also enhanced the inhibition of the enzymes α-amylase (by 5-7 %) and amyloglucosidase (6-9 times more) than free oil (p < 0.05). The results showed that nanoencapsulation increased the potential for quinoa oil application, enabling the development of innovative products.