Lutein liposomes for enhancing lutein delivery stabilized by stigmasterol: Preparation, characterization and release in vitro

Stigmasterol presents a promising approach for developing healthier, cholesterol-free lutein-loaded liposomes. Lutein liposomes were prepared with varying stigmasterol proportions using the ethanol injection method, and their particle size, encapsulation efficiency, stability, in vitro release, and bioavailability were evaluated. The results demonstrated that stigmasterol significantly enhanced the physicochemical stability of lutein liposomes. At a soy lecithin to stigmasterol ratio of 9:1, the liposomes achieved the highest encapsulation efficiency (88.23 %) and a bioavailability of 21.69 %, along with good stability after 7 days of storage and over 60 % lutein retention. Stigmasterol promotes an orderly arrangement of liposome membranes, regulates membrane fluidity and permeability, and enhances the formation of a dense, structurally stable phospholipid bilayer. This study underscores stigmasterol's potential as a key component in phytosterol-modified liposomes, with promising applications in functional food ingredients and delivery systems.