title: Variations in insecticidal activity and chemical compositions of leaf essential oils from Cryptomeria japonica at different ages.
abstract: The larvicidal effects of the essential oils extracted from the leaves of Cryptomeria japonica at different ages (58, 42, and 26 years old) against 2 mosquito species, Aedes aegypti and Aedes albopictus, were studied. The analysis of major constituents of these essential oils was also investigated. Results obtained from the larvicidal tests, using essential oil from the leaves of 58-year-old C. japonica was found to be most effective against both A. aegypti and A. albopictus larvae, indicating tree age has significant influence on mosquito larvicidal activity. In addition, the eleven pure constituents from C. japonica leaf essential oil were also tested individually against the two mosquito larvae. Among them, alpha-terpinene, gamma-terpinene, p-cymene, 3-carene, terpinolene, and beta-myrcene shows strong larvicidal effect against the two mosquito larvae. Among these pure constituents, 3-carene exhibits the best larvicidal effect against A. aegypti and terpinolene shows an excellent inhibitory action against A. albopictus larvae. The results of this study show that the leaf essential oil and its effective constituents might be considered as a potent source for the production of fine natural larvicides.
authors.affiliation: The Experimental Forest, National Taiwan University, Nan-Tou, Taiwan.
authors.forename: Sen-Sung
authors.initials: SS
authors.lastname: Cheng
authors.forename: Meng-Thong
authors.initials: MT
authors.lastname: Chua
authors.forename: Ed-Haun
authors.initials: EH
authors.lastname: Chang
authors.forename: Chin-Gi
authors.initials: CG
authors.lastname: Huang
authors.forename: Wei-June
authors.initials: WJ
authors.lastname: Chen
authors.forename: Shang-Tzen
authors.initials: ST
authors.lastname: Chang
mesh_terms: D000375:Aging / Q000187:drug effects*; D000818:Animals; D032485:Cryptomeria / Q000145:classification / Q000378:metabolism; D009033:Culicidae / Q000187:drug effects* / Q000254:growth & development* / Q000502:physiology; D007306:Insecticides / Q000008:administration & dosage* / Q000737:chemistry*; D007814:Larva / Q000187:drug effects / Q000254:growth & development; D009822:Oils, Volatile / Q000737:chemistry* / Q000494:pharmacology*; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry; D018515:Plant Leaves / Q000145:classification / Q000378:metabolism*; D015996:Survival Rate
chemical_list: D007306:Insecticides; D009822:Oils, Volatile; D010936:Plant Extracts