ABSTRACT Separation of active components from essential oils is very difficult due to some similar chemical and physical properties. In this work, a facile method is developed to reduce the separation cost. β-Cyclodextrin (β-CD) is used for the separation of eugenol and eugenol acetate by forming the inclusion complexation of non-covalent host–guest interactions. The separation was achieved by a co-precipitation method, using ethanol:water (1:4, v/v) as a solvent at the temperature of 50 °C for 2 h. The molar ratio of guests to β-CD for complexation was 4:1. The inclusion rate of eugenol increased to 60% with a separation factor of 2.5, and the purity of eugenol was up to 99% from 50% after one cycle. β-CD can be easily recovered with industrial ethanol (95%,v/v) and used repeatedly. A possible mechanism is also proposed based on the experimental and computational methods. The results indicate that β-CD is suitable to separate the aromatic constituents from the natural products. Graphical abstract Selectively separate eugenol from eugenol acetate, which was attributed to the difference of weak interactions between guests and β-CD, i.e. hydrogen bonding interaction.

中文翻译：

---

以β-环糊精为选择性溶剂有效分离丁香酚和乙酸丁香酚的机理

摘要 由于一些相似的化学和物理特性，从精油中分离活性成分非常困难。在这项工作中，开发了一种简便的方法来降低分离成本。β-环糊精 (β-CD) 用于通过形成非共价主客体相互作用的包合络合来分离丁香酚和丁香酚乙酸酯。分离是通过共沉淀法实现的，使用乙醇：水（1：4，v/v）作为溶剂，在 50°C 的温度下保持 2 小时。用于络合的客体与 β-CD 的摩尔比为 4:1。丁香酚的包合率提高到60%，分离因子为2.5，经过一个循环后丁香酚的纯度由50%提高到99%。β-CD 可以很容易地用工业乙醇 (95%, v/v) 回收并重复使用。还基于实验和计算方法提出了一种可能的机制。结果表明β-CD适用于从天然产物中分离芳香成分。图文摘要 选择性分离丁香酚和醋酸丁香酚，这是由于客体与β-CD之间弱相互作用的差异，即氢键相互作用。