The effects of microwave inducement towards inclusion complex formation by nanoencapsulation of linalool

Linalool, a chiral alcohol terpene, possesses distinctive odor profiles due to its enantiomers which are lavender-like (R)-linalool and herbaceous (S)-linalool.It is commonly found and used in wine, cosmetics, and aromatic products.However, products containing linalool may suffer from short shelf life due to its high volatility.Improving the stability and creating an ability to control the enantiomeric ratio of linalool can enhance the shelf life and alter the odor profile of the final products.For the stability improvement, nanoencapsulation with beta-cyclodextrin (-CD) can be introduced with the added benefit of altering the enantiomeric ratio of linalool.In this study, microwave inducement at 300 W for 5 s was introduced during the complex formation process to induce rotational motions of linalool.The results showed that microwave inducement improved the encapsulation efficiency from 50.70% to 59.42%.This is probably due to the induced rotation of linalool molecules which increases the probability of proper alignments of the host and guest molecules.In addition, results from GC-FID showed that microwave inducement increased the composition of (R)-linalool in the inclusion complex from 49.87% to 52.10%.Results from semi-empirical PM7 calculations with 2:2 host:guest ratio showed that the RR/Dimer had lower complexation energy and was more balanced in terms of charge distribution.The increase in stability of RR/Dimer suggests that the binding between (R)-linalool dimers and -CD is preferred, which leads to the higher enantiomeric selectivity towards (R)-linalool in the inclusion complex.