Freeze-Dried Liposomes as Carriers of Eugenia pyriformis Cambess Phytoactives for Cosmetic Applications

The demand for phytoactives in cosmetics is growing due to their potential as safer and sustainable alternatives to synthetic compounds. The fruit pulp of Eugenia pyriformis Cambess (uvaia), a species native to the Atlantic Forest, is rich in phenolic compounds and ascorbic acid, with high antioxidant activity, making it a promising active ingredient for cosmetic applications, particularly in skin anti-aging formulations. This study aimed to extract bioactives from uvaia fruit, evaluate their antioxidant properties, and develop freeze-dried liposomes to enhance their stability and physicochemical characteristics. Uvaia pulp was freeze-dried and extracted via dynamic maceration using water (EX.AQ) and 70% ethanol (EX.ET). EX.ET exhibited the highest polyphenol content (16.44 ± 0.95 mg GAE/g dry basis) and antioxidant activity (IC50 = 122.09 ± 5.28 µg/mL). Liposomes containing EX.ET (F1-EX) and blank liposomes (F1-B) were prepared using an adapted ethanol injection method and freeze-dried with two cryoprotectant mixtures: A1 (trehalose, mannitol, and colloidal silicon dioxide) and P1 (whey protein and colloidal silicon dioxide). F1-EX liposomes had a larger particle size (232.50 ± 2.72 nm) than F1-B (143.90 ± 2.80 nm), with similar polydispersity (PdI < 0.30) and zeta potential (>30 mV). The encapsulation efficiency of F1-EX reached 58.8 ± 0.5%. Freeze-dried liposomes showed low water activity (0.068–0.340) and moisture content (2.71–3.58%), while cryoprotectant A1 resulted in a lower PdI (0.144 ± 0.039) and higher zeta potential (−39.00 ± 0.44). These results demonstrate that uvaia is a valuable source of bioactive substances, with encapsulation and drying technologies enhancing their stability and functionality, making them suitable for potential applications in the pharmaceutical and cosmetic sectors. Furthermore, this approach supports the sustainable use of natural resources and contributes to preserving Brazil’s biodiversity.