o:36809 Ergosterol-Enriched Liposomes with Post-Processing Modifications for Serpylli Herba Polyphenol Delivery: Physicochemical, Stability and Antioxidant Assessment en Background/Objectives: In the present study, ergosterol, a novel natural and animal-free alternative sterol, was investigated, and its effects on liposomal properties were assessed. Importantly, ergosterol’s fungal origin offers a sustainable substitute for cholesterol, aligning with current trends in natural and vegan-friendly formulations. Methods: This study explored the effect of ergosterol content (10 mol% vs. 20 mol%) on the encapsulation efficiency (EE), physical properties, morphology, antioxidant activity, lipid peroxidation, and storage stability of Serpylli herba extract-loaded liposomes. Results: Liposomes with 20 mol% ergosterol exhibited significantly higher EE (~81.0%) than those with 10 mol% (~75.6%), along with improved resistance to UV- and freeze-drying-induced reduction in EE. Extract loading resulted in a reduced particle size, indicating favorable bilayer interactions, whereas lyophilization increased size and polydispersity, reflecting structural destabilization. However, 20 mol% ergosterol improved vesicle uniformity and surface charge stability, suggesting enhanced bilayer rigidity. Zeta potential and mobility trends supported improved colloidal stability in ergosterol-enriched systems under all tested conditions. Over 28 days at 4 °C, non-treated extract-loaded liposomes with a higher ergosterol content demonstrated enhanced vesicle integrity. During storage, UV-treated and lyophilized liposomes with 20 mol% ergosterol maintained more consistent size and charge profiles, indicating better membrane reorganization and stability. Nanoparticle tracking analysis demonstrated that ergosterol content modulates vesicle concentration in a dose-dependent manner, highlighting the role of membrane composition in liposome formation and potential dose uniformity. Transmission electron microscopy analysis of extract-loaded liposomes demonstrated well-defined vesicles with intact structural features. A study in a Franz diffusion cell revealed that ergosterol-enriched liposomes significantly delayed polyphenol release compared to free extract, confirming their potential for controlled delivery. Antioxidant activity was preserved in all liposomal systems, with higher ergosterol content supporting improved ABTS radical scavenging potential after stress treatments. FRAP assay results remained stable across formulations, with no major differences between sterol levels. TBARS analysis demonstrated that Serpylli herba extract significantly reduced UV-induced lipid peroxidation in ergosterol-enriched liposomes, underscoring its protective antioxidant role. Conclusions: Higher ergosterol content enhanced liposomal performance in terms of encapsulation, structural resilience, and antioxidant retention, particularly under UV and lyophilization stress. Ergosterol-containing liposomes exhibited improved stability, favorable particle size distribution, and high encapsulation efficiency, while maintaining the antioxidant functionality of the incorporated Serpylli herba polyphenol-rich extract. These findings highlight the potential of ergosterol-based liposomes as robust carriers for bioactive compounds in pharmaceutical and nutraceutical applications that align with current trends in green and vegan-friendly formulations. ergosterol; liposomes; polyphenol antioxidants; rheology; stability; Serpylli herba 1552099 https://doi.org/10.3390/pharmaceutics17111362 2025-10-22T12:44:54.580Z 44 yes 46 Aleksandra A. Jovanović University of Belgrade, Institute for the Application of Nuclear Energy, Serbia doktor tehnoloških nauka 0000-0001-5394-0125 Predrag Petrovic Innovation Center, the Faculty of Technology and Metallurgy, University of Belgrade, 11000 Belgrade, Serbia person Andrea Pirković University of Belgrade, Institute for the Application of Nuclear Energy INEP, Serbia doktor bioloških nauka person 0000-0002-1182-4895 Ninoslav Mitić University of Belgrade, Institute for the Application of Nuclear Energy INEP, Serbia doktor bioloških nauka person 0000-0003-2756-6517 Francesca Giampieri Department of Clinical Sciences, Università Politecnica delle Marche, 60131 Ancona, Italy; Joint Laboratory on Food Science, Nutrition, and Intelligent Processing of Foods, Polytechnic University of Marche, Italy, Universidad Europea del Atlántico, Spain, and Jiangsu University, China, Università Politecnica delle Marche, 60131 Ancona, Italy; Research Group on Food, Nutritional Biochemistry and Health, Universidad Europea del Atlántico, Isabel Torres 21, 39011 Santander, Spain person Maurizio Battino Department of Clinical Sciences, Università Politecnica delle Marche, 60131 Ancona, Italy; Joint Laboratory on Food Science, Nutrition, and Intelligent Processing of Foods, Polytechnic University of Marche, Italy, Universidad Europea del Atlántico, Spain, and Jiangsu University, China, Università Politecnica delle Marche, 60131 Ancona, Italy; Research Group on Food, Nutritional Biochemistry and Health, Universidad Europea del Atlántico, Isabel Torres 21, 39011 Santander, Spain; International Joint Research Laboratory of Intelligent Agriculture and Agri-Products Processing, Jiangsu University, Zhenjiang 212013, China person Dragana Dekanski University of Belgrade, Institute for the Application of Nuclear Energy INEP, Serbia doktor medicinskih nauka person 0000-0001-8467-4165 application/pdf 3924426 https://phaidrabg.bg.ac.rs/o:36809 no yes 16 70 92000001 11A29 Ergosterol-Enriched Liposomes with Post-Processing Modifications for Serpylli Herba Polyphenol Delivery: Physicochemical, Stability and Antioxidant Assessment 1362 17 11 Pharmaceutics Basel, Switzerland MDPI 2025