【摘要】 在杜仲树中杜仲胶以晶体微粒的形式存在,必需用溶剂提取或机械破坏植物组织来获取。虽然溶剂法的效率更高,但溶剂的消耗量大,污染环境严重。我们的研究发现,杜仲胶在热的石油醚中(约80℃)有很高的溶解度,冷却到40℃时有胶丝析出,当温度降到-20℃以下,杜仲胶几乎能较完全从石油醚中析出,回收的溶剂可继续用于下一次杜仲胶的提取,溶剂可循环使用。由于其他杂质仍以溶解态保留在溶剂中,回收的杜仲胶纯度高。此外,整个实验方法的溶剂损失少,对环境的污染小,制备方法简便。更多还原

【Abstract】 Eucommia ulmoides gum(gutta-percha or balata) is a crystalline particle existing in the bark and leaf of Duzhong tree (Eucommia ulmoides Oliv),and to extract E.ulmoides gum,some special methods have to be used.The involved methods can be divided into two classes:solvent resolution and mechanical force destroying plant tissue.Although solvent resolution method has a high efficiency,the currently used methods require a great deal of amount solvent and cause a serious environmental pollution.The results showed that E.ulmoides gum was easily resolved in hot(about 80 ℃) petroleum ether,but when the temperature of solution cooled down to below 40 ℃,flocculent gum turned up and at-20 ℃gum in solution almost fully precipitated out.After filtering off gum,the solution was well reused as a solvent for next gum extraction.Since the other impurities were kept in solution,deposited flocculent gum had a high purity.And also in experiment process,the loss of solvent was small and caused pollution in surroundings was limited,and new method greatly simplified the gun extraction and recovery process.更多还原