植物甾醇和核桃油复配的纳米结构脂质载体的制备及其稳定性研究

本研究通过高压均质法采用核桃油为液体脂质制备用于封装、保护植物甾醇(Phytosterol,PS)的纳米结构脂质载体(Nanostructured lipid carriers,NLC)。以平均粒径、多分散指数、Zeta电位及包封率等为主要评价指标,对制备工艺参数及配方进行优化,同时对优化后的PS-NLC进行形貌观察及稳定性研究。通过正交试验确定制备PS-NLC的最佳比例为总脂质浓度10%,硬脂酸和核桃油的比例为2:3,大豆卵磷脂浓度为1.2%。制备得到的PS-NLC外观呈球形,粒径较小且分布均匀。PS-NLC的稳定性结果表明:PS-NLC在4℃下储藏28 d稳定性良好;在使用时可以在5～100倍之间进行稀释,具有良好的稀释稳定性;添加2%的蔗糖对PS-NLC的冻干保护效果最佳。本文利用核桃油作为NLC的壁材为植物甾醇提供了一个合适的脂质运载系统,可为食品工业构建PS-NLC提供技术支持。

Preparation and Stability of Nanostructured Lipid Carriers of Phytosterols with Walnut Oil

Nanostructured lipid carriers (NLC) for the encapsulation and protection of phytosterol (PS) were prepared using walnut oil as liquid lipid by high-pressure homogenization method. The average particle size, polydispersity index, Zeta potential and encapsulation efficiency were used as the main evaluation indexes to optimize the preparation process parameters and formulations, and the morphology and stability of the optimized PS-NLC were investigated. The optimal ratio for the preparation of PS-NLC was determined by orthogonal tests as 10% of total lipid concentration, 2:3 of stearic acid and walnut oil, and 1.2% of soy lecithin. The prepared PS-NLC had a spherical appearance, small particle size and uniform distribution. The stability results of PS-NLC showed that PS-NLC was stable in storage at 4 ℃ for 28 days. It was diluted 5~100 times with good dilution stability, when used. And the addition of 2% sucrose had the best effect on the lyophilization protection of PS-NLC. Walnut oil was used as the wall material of NLC to provide a suitable lipid delivery system for phytosterols, which could provide technical support for the construction of PS-NLC in food industry.