Abstract The low bioavailability of polyphenol limits their use in functional foods. This study focused on the effects of luteolin, quercetin, proanthocyanidins, and apigenin loading on the attributes of lipid bilayers. Liposomes loaded with quercetin and proanthocyanidins were smaller in size and disperse more uniformly than those loaded with luteolin and apigenin. The spherical structures of these four liposomes were investigated via transmission electron microscope (TEM) and atomic force microscope (AFM). Raman spectra showed that the choline groups in all the liposome bilayers were mainly gauche conformations. Furthermore, polyphenolics had different effects on the liposomes' mobility and structure, which were dependent on the localization and orientation of polyphenolics in the lipid bilayer. X-ray diffraction (XRD) analysis indicates that four kinds of polyphenolics exist in an amorphous form in these liposomes. Fluorescence analysis indicates that the four polyphenolic compounds could load into the liposomes with different orientations. The ability of the four polyphenols to chelate Al3+ was significantly reduced in the lipid environment. The results reveal that polyphenolics' localization in lipid bilayers and their effects on lecithin membranes can be attributed to the polyphenols’ structural characteristics. These were vital factors that should be taken into account when designing a liposome delivery system.

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四种多酚负载量对脂双层特性的影响

摘要 多酚的低生物利用度限制了它们在功能性食品中的应用。本研究侧重于木犀草素、槲皮素、原花青素和芹菜素负载对脂质双层属性的影响。装载槲皮素和原花青素的脂质体比装载木犀草素和芹菜素的脂质体更小，分散更均匀。通过透射电子显微镜 (TEM) 和原子力显微镜 (AFM) 研究了这四种脂质体的球形结构。拉曼光谱表明所有脂质体双层中的胆碱基团主要是gauche构象。此外，多酚对脂质体的迁移率和结构有不同的影响，这取决于多酚在脂质双层中的定位和取向。X 射线衍射 (XRD) 分析表明，在这些脂质体中，四种多酚以无定形形式存在。荧光分析表明四种多酚化合物可以以不同的方向加载到脂质体中。四种多酚螯合 Al3+ 的能力在脂质环境中显着降低。结果表明，多酚在脂质双层中的定位及其对卵磷脂膜的影响可归因于多酚的结构特征。这些是设计脂质体递送系统时应考虑的重要因素。四种多酚螯合 Al3+ 的能力在脂质环境中显着降低。结果表明，多酚在脂质双层中的定位及其对卵磷脂膜的影响可归因于多酚的结构特征。这些是设计脂质体递送系统时应考虑的重要因素。四种多酚螯合 Al3+ 的能力在脂质环境中显着降低。结果表明，多酚在脂质双层中的定位及其对卵磷脂膜的影响可归因于多酚的结构特征。这些是设计脂质体递送系统时应考虑的重要因素。