Department of Food Science and Technology, Universidad de Santiago de Chile, USACH, Avenida Ecuador 3769, Santiago, Chile.
Department of Food Science and Technology, Universidad de Santiago de Chile, USACH, Avenida Ecuador 3769, Santiago, Chile.
Food Res Int. 2020 Apr;130:108967. doi: 10.1016/j.foodres.2019.108967. Epub 2019 Dec 29.
The potential use of liposomes as carriers for food active ingredients can be limited by their physical and chemical instabilities in aqueous dispersions, especially for long-term storage. Lyophilization, a process commonly used in the food industry, can also be applied to stabilize and preserve liposomes and to extend their shelf-life. In this work, liposomes with potential use for designing functional foods were prepared with soy phospholipids and rutin. Homogenization and ultrasound were used for particle size reduction. Liposomal stability was evaluated by Dynamic Light Scattering, microscopy and rheological properties. Spherical and unilamellar liposomes were obtained in this work. Zeta potential (ξ = values were around -40 mV), which indicates a great suspension stability even for more than 30 days of storage. Rutin exerted a protective effect by both preventing damage to the liposome bilayer and maintaining the spherical structure after 56 days of storage. Lyophilization caused an increase in the size of the vesicles, reaching sizes around 419 nm and aggregation of vesicles with probably structural damage after 21 storage days. However, it helped to keep the rutin encapsulated (81.9%) for longer time, when compared to refrigerated liposomes. Rheological measurements showed, in general, that the power law model fitted most of the experimental results and dynamic rheological tests showed a sol-gel phase transition between 35 and 45 °C. Lyophilization caused a significant change in all evaluated rheological parameters. For the in vitro release tests, the liposomal bilayer acted as a barrier for the rutin release to the food simulating medium; therefore, the release rate of the antioxidant from the rutin encapsulated liposome was slow compared to the free rutin release rate.
脂质体作为食品活性成分载体的潜在用途可能受到其在水相分散体中的物理和化学不稳定性的限制，特别是对于长期储存。冷冻干燥是食品工业中常用的一种工艺，也可用于稳定和保存脂质体，并延长其保质期。在这项工作中，使用大豆磷脂和芦丁制备了具有功能性食品设计潜力的脂质体。采用均质化和超声处理来减小粒径。通过动态光散射、显微镜和流变特性评估脂质体的稳定性。在本工作中获得了球形和单分子层脂质体。Zeta 电位（ξ）值约为-40 mV，表明即使在储存超过 30 天后，悬浮液仍具有很好的稳定性。芦丁通过防止脂质体双层损伤和在储存 56 天后保持球形结构发挥了保护作用。冷冻干燥会导致囊泡尺寸增大，达到约 419nm 的尺寸，并在储存 21 天后发生囊泡聚集和可能的结构损伤。然而，与冷藏脂质体相比，它有助于更长时间地保持包封的芦丁（81.9%）。流变学测量结果表明，一般来说，幂律模型最适合大多数实验结果，动态流变学测试显示在 35 和 45°C 之间发生溶胶-凝胶相转变。冷冻干燥导致所有评估的流变学参数发生显著变化。对于体外释放试验，脂质体双层作为芦丁向食品模拟介质释放的屏障；因此，与游离芦丁的释放速率相比，包封在脂质体中的芦丁的释放速率较慢。
