Yuan Jiao-Jiao, Qin Frank G F, Tu Jun-Ling, Li Bing
School of Chemical Engineering and Energy Technology, Dongguan University of Technology, Dongguan 523808, China.
School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China.
Molecules. 2017 May 24;22(6):870. doi: 10.3390/molecules22060870.
Due to the multiple hydroxyl groups in its structure, hydroxytyrosol (HT) is very sensitive to air and light and has very strong instability and hydrophilicity that affect its biological activity. This study attempted to prepare liposomes containing water-soluble HT to improve the bioavailability and biocompatibility of the target drug. The preparation process factors (temperature, mass ratio of phospholipid (PL) and cholesterol (CH), Tween-80 volume, HT mass) were studied and response surface methodology (RSM) was applied to optimize the conditions. The results demonstrated that by using a temperature of 63 °C, mass ratio of PL and CH 4.5:1, HT mass 5 mg and Tween-80 volume of 6 mL, HT liposomes with an encapsulation efficiency (EE) of 45.08% were prepared. It was found that the particle sizes of the HT liposomes were well distributed in the range of 100-400 nm. Compared to free HT, prepared HT liposomes had better stability and a distinct slow release effect in vitro. Besides, HT liposomes presented better DPPH radical scavenging activity than free HT, which could be due to the fact that HT was encapsulated fully inside the liposomes. In addition, the encapsulation mechanism of HT was evaluated. In summary, the results indicated that HT liposome could enhance the antioxidant activity and was a promising formulation for prolonging the biological activity time of the target drug.
由于其结构中存在多个羟基，羟基酪醇（HT）对空气和光非常敏感，具有很强的不稳定性和亲水性，这会影响其生物活性。本研究试图制备含有水溶性HT的脂质体，以提高目标药物的生物利用度和生物相容性。研究了制备工艺因素（温度、磷脂（PL）与胆固醇（CH）的质量比、吐温-80体积、HT质量），并应用响应面法（RSM）优化条件。结果表明，在温度为63℃、PL与CH质量比为4.5:1、HT质量为5mg、吐温-80体积为6mL的条件下，制备出包封率（EE）为45.08%的HT脂质体。发现HT脂质体的粒径在100-400nm范围内分布良好。与游离HT相比，制备的HT脂质体具有更好的稳定性和明显的体外缓释效果。此外，HT脂质体的DPPH自由基清除活性比游离HT更好，这可能是因为HT被完全包裹在脂质体内。此外，还评估了HT的包封机制。总之，结果表明HT脂质体可以增强抗氧化活性，是延长目标药物生物活性时间的一种有前景的制剂。
