索氏抽提——溶剂结晶法纯化银杏叶提取物中银杏内酯的研究

建立了基于索氏抽提和溶剂结晶法的高纯度银杏内酯混合物提取纯化工艺.利用单因素实验选定乙酸乙酯作为索氏抽提法的萃取溶剂,再组建L16（45）正交实验获得索氏抽提最佳条件：浸提时间5 min、淋洗时间10 min、热源温度170℃、液固比12.在此条件下,内酯提取率可达84%,纯度可达42%.而后通过常温粗结晶1 h,-20℃重结晶1 h的步骤,可获得纯度大于97%的银杏内酯A、B、C混合物,内酯总得率约43%.该法简单易行、成本低廉且污染小,能够满足实验室日常制备或工业化批量生产的需求.

On the Textual Criticism Learning Features in the Literature Teaching of Gujing Jingshe

A novel method based on soxhlet extraction and crystallization for the purification of ginkgolide mixture was established.A single factor experiment and a L16（45） orthogonal experiment were established to determined the optimum solvent and the best extracting conditions for soxhlet extraction,separately.The results shown that： the optimum solvent for the extraction process was EtOAc;and the best conditions for the soxhlet extraction involved a immersion time of 5 min,a washing time of 10 min,a working temperature of 170℃ and a liquid-solid ratio of 12.Under such conditions,the extraction rate of ginkgolide could reach 84% and the purity could be 42%.A mixture of GA,GB and GC whose purity was 97% and yield rate was 43% could be extracted from this product,followed by 1 hour of crystallization process at room temperature,and 1 hour of crystallization process at-20℃.The method was proved simple,economical and almost free of pollution,it can be applied to the daily prepare of ginkgolide by laboratory or the large scale production of industry.