梨叶多酚提取的正交试验优化及其成分测定

以早酥梨成熟叶片为研究对象，考察超声时间、料液比、溶剂种类3 个因素对梨叶多酚提取效果的影响，以优化梨叶片多酚提取工艺，并采用超高效液相色谱-光电二极管阵列技术，测定梨叶片多酚物质组成和含量。结果表明：梨叶片中熊果苷最佳提取条件是：采用70%甲醇溶液提取溶剂、超声（超声功率500 W）辅助提取2 次、每次超声时间30 min、料液比1∶150 （g/mL）；梨叶片中咖啡酰奎宁酸类和黄酮醇类的最佳提取条件均是：超声（超声功率500 W）辅助提取2 次、每次超声时间25 min、采用70%甲醇溶液提取溶剂、料液比1∶125 （g/mL）。在优化的提取条件下，梨叶中共检测出10 种多酚物质，其中熊果苷含量最高为7.934～36.854 mg/g，被检测出的多酚物质总含量高达17.852～61.149 mg/g，因此梨叶片可作为开发化妆品、保健品和药品的优质天然材料。

Optimization of Extraction of Pear Leaf Polyphenols by Orthogonal Array Design and Polyphenol Composition Analysis

The ultrasonic-assisted extraction of polyphenols from mature leaves of Zaosu pear was optimized by
investigating the effects of ultrasonic time, solid-to-solvent ratio and solvent type on extraction efficiency. The components
and contents of pear leaf polyphenols were determined by ultra performance liquid chromatography (UPLC) coupled with
photodiode array detector (PDA). The results showed that the optimal conditions for arbutin extraction from pear leaves were
found to be 30 min extraction carried out twice using 70% aqueous ethanol as the extraction solvent with a solid-to-solvent
ratio of 1:150 (g/mL) at an ultrasonic power of 500 W, while the optimal conditions for the extraction of both caffeoylquinic
acid and flavonols were identical to those for arbutin except for an extraction time of 25 min and a solid-to-solvent ratio
of 1:125 (g/mL). Ten polyphenols were detected in pear leaves under the optimized conditions with total contents ranging
from 17.852 to 61.149 mg/g, and the contents of arbutin were 7.934–36.854 mg/g. Therefore, pear leaves can be used as an
excellent natural material for developing cosmetics, health products and medicines.