Identification of Repellent and Insecticidal Constituents fromArtemisia mongolicaEssential Oil againstLasioderma serricorne
The aims of this research were to determine the chemical composition and insecticidal and repellent activities of theArtemisia mongolicaessential oil againstLasioderma serricorneand to isolate active constituents from the essential oil. The essential oil ofA. mongolicawas obtained by hydrodistillation and 36 components were identified with GC-MS. Eucalyptol (39.88%), (S)-cis-verbenol (14.93%), 4-terpineol (7.20%), (−)-camphor (6.02%), andα-terpineol (4.20%) were found to be major components. With a further isolation process, five constituents obtained from the essential oil were identified as eucalyptol, verbenol, 4-terpineol, camphor, andα-terpineol. In the progress of assay, it showed thatL. serricorneadults had different sensitivities to the crude essential oil and isolated constituents. 4-Terpineol exhibited strongest contact activity againstL. serricorne, showing the LD50value of 8.62 μg/adult. Moreover, camphor andα-terpineol showed stronger fumigant activity (LC50=2.91and 3.27 mg/L air, resp.) againstL. serricornethan crude essential oil and other constituents. In addition, the essential oil, eucalyptol, verbenol, andα-terpineol showed comparable repellency againstL. serricorneadults. The results indicate that the essential oil and isolated compounds have potential to provide more efficient and safer natural insecticides or repellents for control of insects in food and Chinese medicinal materials preservation.