β-谷甾醇脂质体包载乳源活性成分的研究

Studies on β-sitosterol liposome encapsulation of milk-borne bioactive components

以大豆卵磷脂和植物甾醇为包封材料，用薄膜法制备胰岛素脂质体，用凝胶层析法分离脂质体与游离胰岛素并测定目标组分包封率。当卵磷脂与β-谷甾醇质量比为1．75：1，胰岛素溶液质量浓度为2．0g／L，制备温度为42．3℃时，包封率达到53．8％。显微观察显示β-谷甾醇脂质体为典型的球状多室形态，平均粒径约3．086μm。在模拟人体消化体系中，该脂质体包载可提高生物活性成分对酸、酶的抵抗能力。该脂质体制剂应用于牛奶体系，可耐受巴氏消毒处理（63-65℃／30min），在冷藏条件下最初7d内具有很好的稳定性，8-9d后脂质体之间发生聚集、融合，分散悬浮稳定性显著降低。β-谷甾醇-卵磷脂脂质体具有作为乳源活性成分强化载体的潜力。

Human Insulin was encapsulated by soybean phosphatidyl choline and phytosterol liposomes in the thin film hydration. Subjected to CL-4B gel chromatography, hposomes separated from free proteins and the encapsulation rate could be determined. The conditions to obtain the higher encapsulation rate （53.8%） included： the mass rate of soybean phosphatidyl chohne andβ-sitosterol 1.75：1, the Insulin concentration 2.0 mg. mL^-1, preparation temperature 42.3 ℃. The microscopical observation and particle size analysis showed these liposomes were typical multilameUar morphology with an average diameter of around 3.086 mm. The activity of encapsulated bioactive component survived better in mimic gastrointestinal digestive system than the free components. The hposomal products added in milk can survive pasteurization （63-65 ℃/30 min）, showed excellent dispersion stability in the first 7 days during cold storage, however, the system destabilized and amalgamation of liposomal particles happened after 8-9 days. This study suggested that β-sitosterol-phosphatidyl choline hposome had a potential to be used as a fortifying carrier of milk-borne bioactive components.