Characterization of tea tree essential oil and large-ring cyclodextrins(CD9 -CD22 )inclusion complex and evaluation of its thermal stability and volatility.

BACKGROUND Although the structure and physicochemical properties of large ring cyclodextrins (LR-CDs) exhibit unique characteristics, and possess very strong water solubility and high safety, little is known about the embedding performance of macrocyclodextrin . Encapsulation refers to complex of tea tree oil (TTO) with the wall material , protecting the core material or changing its properties from adverse external factors , controlling its release rate against the evaporation and degradation of essential oils . In this paper , LR-CDs complexed with TTO were prepared by co-precipitation methods. RESULTS The mass ratio of LR-CDs / TTO was six , and the maximum complexation efficiency was 86.23 %. FT-IR analysis presented the loss of characteristic peaks related to TTO in the complex and no other additional peaks were observed. X-ray diffraction examination demonstrated several sharp peaks and intensity peaks at the diffraction angle of the TTO-LR-CDs complex. 1 H NMR indicated the chemical shift due to the interaction between the molecules in the inclusion complex . Moreover, the thermal stability and aqueous solubility of TTO were enhanced after synergy with LR-CDs, particularly , the solubility of the complex was increased 329-fold. The volatile characteristics of the encapsulated and original TTO were identical . CONCLUSION These results showed that TTO was efficaciously complexed with LR-CDs and exhibited enhanced solubility and thermal stability. This article is protected by copyright. All rights reserved.