Abstract
The influence of linear alcohols on the formation of inclusion complexes between d-limonene and α-, β-, or γ-cyclodextrin has been examined at a low water content using a micro-aqueous method. In the presence of alcohols, particularly methanol and ethanol, the formation of inclusion complexes between d-limonene and β- or γ-cyclodextrin is enhanced. The alcohol included in the cyclodextrin at the low water content was replaced with d-limonene as the water content increased. This implies that these alcohols would behave like water and activate the inclusion reaction between d-limonene and β- or γ-cyclodextrin. On the contrary, the formation of -limonene complexes with α-cyclodextrin is inhibited by the presence of alcohols except for methanol. By means of the apparent water content, the amount of d-limonene complex in β- and γ-cyclodextrin correlated well with a single sigmoid curve.
