부산대학교 도서관

Cinnamomum osmophloeum Kaneh. ct. linalool is one chemotype of the indigenous cinnamon in Taiwan. In this study, hydrodistillation was used for extracting the leaf essential oil (LEO) of C. osmophloeum ct. linalool collected from various plants and seasons, and GC-MS and GC-FID were used to examine variations and contents of chemical composition in LEOs. Moreover, the absolute configuration of the main constituent and its content of LEO were illustrated by GC-FID with chiral column. In addition, we also investigated the effect of the extraction time (1 h, 2 h, 6 h, and 10 h) on the yield of LEO and the content of main constituents. Results from this study revealed that the average LEO yield of 12 plants was 3.7%, and there were more than 90% linalool in them. The linalool in the LEO was proved to be pure S-(+)-linalool and its average content in 12 plants is 31.0 mg. Furthermore, there were no obvious differences in LEO yield and S-(+)-linalool content from various plants and seasons, and the mature leaves have more S-(+)-linalool content. On the other hand, we also identified that LEO and S-(+)-linalool from C. osmophloeum ct. linalool leaves can be completely extracted out by 1 h hydrodistillation. This study recorded the rate of weight changes in mice, and examined the anxiolytic potency of LEO from C. osmophloeum ct. linalool and its main constituent on 4-week ICR mice by using the following animal models, including open field test (OFT), light-dark test (LDT) and elevated plus maze test (EPT). After oral administrations of LEO (250 mg/kg and 500 mg/kg), S-(+)-linalool (500 mg/kg), R-(−)-linalool (500 mg/kg) and trazodone hydrochloride (75 mg/kg) for 14 days, their anxiolytic effects on mice behavior were evaluated, and rate of weight changes were recorded. Brain tissue and blood of the mice were collected after sacrifice for analyses. And then, monoamines in brain tissue sample (frontal cortex, hippocampus and striatum) were measured and blood biochemical values (Glucose, Total cholesterol, Triglyceride, Aspartate aminotransferase (AST) and Alanine aminotransferase (ALT)) in mice blood were also assessed. The results showed that LEO from C. osmophloeum ct. linalool and S-(+)-linalool can significantly increase time spending in the center area of OFT, illuminated area of LDT and open arms of EPT without side effects on locomotor activity, indicating excellent anxiolytic responses. It was also found that the levels of the neurotransmitters (serotonin, dopamine and norepinephrine) decreased in frontal cortex and hippocampus, which could result in the anxiolytic effects in animal models. In addition, mice administrated LEO from C. osmophloeum ct. linalool and S-(+)-linalool have increased the level of dopamine in striatum, indicating that LEO from C. osmophloeum ct. linalool and S-(+)-linalool could be used in Parkinson's disease treatment. We also found that body weight and triglyceride levels of mice after oral administration of S-(+)-linalool was less than control group. The injuries of liver and organ in mice were not observed in this study. The finding obtained suggested that LEO from C. osmophloeum ct. linalool and its major compound, S-(+)-linalool, possess anxiolytic properties without any side effects and thus support their potential uses as cheap and safe additives and health products with anxiolytic effects.