Improving the Long-Term Stability of Carotenoids from Dunaliella Salina Supercritical Fluid Extracts with a New Liposomal Encapsulation Based on Cryogenic and Stirring Processes

Abstract The search for new natural bioactive compounds has recently been intensified; however, some compounds are unstable under atmospheric conditions, suffering degradation and loss of bioactivity. Encapsulation is a strategy employed in the food industry to enhance the stability of such labile compounds. This study presents a novel microencapsulation method for preserving terpene-rich extracts from the microalga Dunaliella salina with potential neuroprotective activity. Microliposomes were formed using phosphatidylcholine as encapsulating agent, creating a nanoemulsion stabilized by lyophilization. A purification step yielded a pure encapsulated product with an efficiency of 63%. The behavior of key compounds, particularly terpenes and carotenoids, was analyzed throughout the encapsulation process. Low molecular weight terpenes were the most affected by processing temperatures, while carotenoid encapsulation was linked to their structure-concentration relationship. Stability tests under accelerated storage conditions (45 °C) revealed only a 20% reduction in bioactivity over three months, demonstrating high stability under extreme conditions.