DEVELOPMENT OF NANOEMULSIONS AND NANOSTRUCTURED LIPID CARRIERS CONTAINING BIOACTIVE COMPOUNDS FROM Mugil liza

Bioactive compounds derived from food have become a natural source with the potential for producing functional foods or nutraceuticals. These compounds offer less health risk when compared to synthetic compounds and are a subject of great interest. Among the bioactive compounds can be highlighted the peptides, which have already been associated with different bioactivities. However, for these bioactive compounds to maintain their activity and be gradually released to exercise their functions, avoiding their degradation and oxidation, it is recommended that these be encapsulated. Among the existing technologies, nanoencapsulation increases physical stability, protection, and contact surface, facilitating the solubility and bioavailability of such compounds. In this context, this study aimed to develop lipid nanocarriers containing unsaturated fatty acids and bioactive peptides derived from mullets. The mullet was purchased from a fish market in Rio Grande/RS. To obtain the peptides and extract the oil, enzymatic hydrolysis of the mullet muscle containing skin and spines was performed using the Alcalase 2.4 L for 120 min (pH 8.0 at 58 °C). The separated mullet oil was filtered and hydrolyzed with the enzyme Lipozyme 435. From the hydrolyzed oil fraction, the unsaturated fatty acid concentrate was obtained by separating the saturated fatty acids that were complex with urea. In this study, formulations of nanoemulsions and nanostructured lipid carriers containing cocoa butter, unsaturated fatty acids, and mullet peptides were developed under fixed homogenization conditions (20.000 rpm for 2 min) followed of ultrasound time (10 min). The nanoemulsions and nanostructured lipid carriers were evaluated for size and the polydispersity index. For the evaluation of the antioxidant activity of mullet bioactive peptides after nanoencapsulation two concentrations (3 and 6% w/w) and the following analytical methods were used: DPPH radical scavenging activity (%) and ABTS radical capture (%). The degree of hydrolysis was 14.9 %. The yield of extracted oil was 38.7 %. Mullet oil showed approximately 69.0 % of unsaturated fatty acids. In general, nanoemulsions and nanostructured lipid carriers showed size (189.3 - 225.9 nm) and polydispersity index (0.20-0.24). The antioxidant activity did not show a dose-dependent relationship, being the formulations of nanoemulsions and nanostructured lipid carriers containing 3% (w/w) of peptides showed greater antioxidant activity for the ABTS (66.70-59.20%) and DPPH (38.73-32.37 %), respectively. In this way, it is concluded that mullet can be a source for obtaining antioxidant natural compounds for application in food.