ULTRASOUND-ASSISTED EXTRACTION AND NANOENCAPSULATION OF LYCOPENE: A THERMODYNAMIC AND SUSTAINABLE APPROACH FOR ENHANCED STABILITY AND BIOACCESSIBILITY

Lycopene is a lipophilic carotenoid with high antioxidant potential; however, its application in food systems is limited by its low stability during processing. This study aimed to integrate thermodynamic solvent screening, ultrasound-assisted extraction, and nanoencapsulation to improve lycopene recovery and enhance its stability. Solvent selection was initially performed using the COSMO-SAC (Conductor-like Screening Model for Segmented Activity Coefficients) to estimate activity coefficients at infinite dilution, followed by solid–liquid equilibrium calculations. Ethanol and acetone were selected and experimentally evaluated as mixed solvents. Lycopene was extracted from dried tomato using ultrasound at different temperatures (25-55 °C), extraction times (5-20 min), and ultrasound powers (30 and 100% of nominal power). The selected extract was nanoencapsulated in a polyvinylpyrrolidone matrix by solid dispersion. Antioxidant activity was evaluated by ABTS and DPPH assays before and after standardized in vitro gastrointestinal digestion, while particle morphology and thermal behavior were characterized by Scanning Electron Microscopy (SEM), thermogravimetric analysis, derivative thermogravimetry, and differential scanning calorimetry. COSMO-SAC screening indicated strong lycopene–solvent Affinity for alcohols and ketones, supporting the selection of ethanol and acetone. The ethanol:acetone mixture at 0.5:0.5 (w/w) showed favorable extraction performance, and the selected operational conditions were 50 °C, 5 min, and 30% ultrasound power. Temperature exerted a greater influence on extraction than time, which was associated with enhanced solubility, mass transfer, and ultrasound-induced cavitation. The free extract exhibited the highest antioxidant activity but showed a marked decrease after digestion. In contrast, nanoencapsulation promoted greater relative preservation of antioxidant activity after digestion, indicating a protective effect of the polymeric matrix. SEM revealed well-dispersed micro/submicrometric structures prior to digestion and partial matrix disruption after digestion, consistent with bioactive release. Thermal analyses further confirmed improved stability, with the temperature of maximum degradation rate shifting from approximately 207 °C for the free extract to 457-464 °C for the encapsulated system and polymer matrix. Overall, combining thermodynamic screening, ultrasound-assisted extraction, and nanoencapsulation provided an efficient strategy for lycopene recovery and protection, improving its thermal and gastrointestinal stability and supporting its potential application in functional food systems.

The authors acknowledge the Graduate Program in Food Technology (PPGTA) of the Federal Technological University of Paraná (UTFPR), Campo Mourão campus, and the National Council for Scientific and Technological Development (CNPq). CNPq Call No. 49/2024 – Junior Postdoctoral Fellowship – PDJ 2024, process No. 151797/2025-0.