Potential Source of S-(+)-Linalool from Cinnamomum osmophloeum ct. linalool Leaf: Essential Oil Profile and Enantiomeric Purity
Cinnamomum osmophloeum ct. linalool is one of the chemotypes of the indigenous cinnamon in Taiwan. In this study, hydrodistillation was used for extracting the essential oils (EOs) of C. osmophloeum ct. linalool leaves collected from various plants and seasons, and GC-MS and GC-FID were used to examine variations and contents of the chemical composition in EOs. Moreover, the absolute configuration of the main constituent and its EO content were illustrated by GC-FID with a chiral column. In addition, we also investigated the effect of the extraction time (1, 2, 6, and 10 h) on the yield of EO and the contents of the main constituents. Results from this study revealed that the average EO yield of 12 plants was 3.7%, and linalool accounted for more than 90%. The linalool in the EO was proved to be pure S-(+)-linalool, and its content in the leaves ranged from 28.8 ± 0.3 to 35.1 ± 0.2 mg/g. Furthermore, there were no obvious differences in EO yield and S-(+)-linalool content from various plants and seasons. On the other hand, we also demonstrated that EO and S-(+)-linalool from C. osmophloeum ct. linalool leaves can be completely extracted out by 1 h of hydrodistillation.