山茶油纳米乳液的制备、表征 及抗氧化性分析 Preparation, characterization and antioxidant properties of oil-tea camellia seed oil nanoemulsion

为扩大山茶油的商业应用范围，采用超声技术制备山茶油纳米乳液，通过单因素实验考察了羟丙基-β-环糊精（HP-β-CD）添加量、超声功率和超声时间对纳米乳液粒径和多分散性指数（PDI）的影响，对山茶油纳米乳液的制备工艺进行了优化。通过扫描电子显微镜（SEM）、透射电子显微镜（TEM）、接触角及粒径测定等对山茶油纳米乳液形貌进行表征，并通过傅里叶红外光谱（FT-IR）表征其包埋效果。此外，考察了山茶油纳米乳液的长期物理稳定性和抗氧化性。结果表明：山茶油纳米乳液最佳制备工艺条件为HP-β-CD添加量10%、超声功率500 W和超声时间15 min，在此条件下山茶油纳米乳液的平均粒径为66.01 nm；山茶油纳米乳液外观透明泛蓝光，粒径小且分布均一，HP-β-CD/T80纳米晶的存在可能提高了乳液的稳定性；FT-IR结果表明山茶油被成功包裹；山茶油纳米乳液具有较好的长期物理稳定性，其对DPPH自由基和羟自由基的清除率显著高于同质量分数的山茶油乙醇溶液。综上，山茶油纳米乳液制备工艺简便可行，所得产品稳定性良好，且具有一定的抗氧化性。In order to expand the commercial application range of oil-tea camellia seed oil(CMO), ultrasonic technology was used to prepare CMO nanoemulsion. The effects of hydroxypropyl -β-cyclodextrin (HP-β-CD) addition amount, ultrasonic power and ultrasonic time on the particle size and polydispersity index(PDI) of the nanoemulsion were investigated by single factor experiment to optimize the preparation process of CMO nanoemulsion. The morphology of CMO nanoemulsion was characterized by scanning electron microscopy (SEM), transmission electron microscope(TEM), contact angle and particle size measurements, and the encapsulating effect was characterized by Fourier transform infrared spectroscopy(FT-IR). In addition, the long-term physical stability and antioxidant activity of CMO nanoemulsion were investigated. The results showed that the optimal conditions for preparation of CMO nanoemulsion were obtained as follows: HP-β-CD addition amount 10%, ultrasonic power 500 W and ultrasonic time 15 min. Under these conditions, the average particle size of CMO nanoemulsion was 66.01 nm. CMO nanoemulsion was transparent and bluish in appearance, with small particle size and uniform distribution. The existence of HP-β-CD/T80 nanoparticles might improve the stability of the emulsion. FT-IR characterization showed that CMO was successfully encapsulated. CMO nanoemulsion had good long-term physical stability, and its scavenging rates of DPPH free radical and OH free radical were significant higher than those of CMO-ethanol solution with the same mass fraction of CMO. In conclusion, the preparation process of CMO nanoemulsion is simple and feasible, and the obtained product has good stability and certain antioxidant activity.