Dipalmitoylphosphatidylcholine liposomes were encapsulated with free stigmasterol (ST), stigmasteryl myristate (ME), and stigmasteryl oleate (OE). Their quality was determined using TEM, FT-IR spectroscopy, zeta potential and hydrodynamic diameter. The prepared liposomes were heated at 60 and 180 °C. The degradation of stigmasterol, fatty acids was determined, as was the formation of derivatives. The results show that the liposomes had been prepared successfully. The ST liposomes were the smallest, while the ME and OE liposomes were of similar size. The extent to which the compounds encapsulated in the liposomes degraded depended on their structure. When samples were heated to 60 °C, the degradation of stigmasterol ranged from 11 % in ST to 47 % in OE and 58 % in ME. After heating to 180 °C, the lowest level of degradation of stigmasterol was for OE (51 %), whereas the degradation of stigmasterol in ST and ME was 85 % and 90 %, respectively. In addition, the high level of oxyphytosterols in the samples heated to 180 °C is of concern, especially in the ST and ME samples. The level of SOP in liposomes heated to 60 °C ranged from 1.7 mg/g in liposomes encapsulated with free stigmasterol to 10.4 and 32.9 mg/g in liposomes with stigmasteryl myristate and oleate. After heating to 180 °C, the total content of SOP was much higher, ranging from 68.2 for OE to 111.7 and 135.7 mg/g for ME and ST, respectively.

中文翻译：

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脂质体中封装的豆甾醇及其酯：表征、稳定性和衍生物形成


二棕榈酰磷脂酰胆碱脂质体用游离豆甾醇 （ST）、豆甾酰肉豆蔻酸酯 （ME） 和豆甾酰油酸酯 （OE） 封装。使用 TEM、FT-IR 光谱、zeta 电位和流体动力学直径确定它们的质量。将制备的脂质体在 60 和 180 °C 下加热。 测定豆甾醇、脂肪酸的降解以及衍生物的形成。结果表明脂质体制备成功。ST 脂质体最小，而 ME 和 OE 脂质体大小相似。脂质体中封装的化合物降解的程度取决于它们的结构。当样品加热至 60 °C 时，豆甾醇的降解范围从 ST 中的 11% 到 OE 中的 47% 和 ME 中的 58% 不等。加热至 180 °C 后，OE 中豆甾醇的降解水平最低 （51 %），而 ST 和 ME 中豆甾醇的降解率分别为 85 % 和 90 %。此外，加热至 180 °C 的样品中高水平的氧植物甾醇令人担忧，尤其是在 ST 和 ME 样品中。加热至 60 °C 的脂质体中的 SOP 水平范围从用游离豆甾醇封装的脂质体中的 1.7 mg/g 到具有豆甾醇和油酸酯的脂质体中的 10.4 和 32.9 mg/g。加热至 180 °C 后，SOP 总含量远高于 OE 的 68.2 至 ME 和 ST 的 111.7 和 135.7 mg/g。