Use of novel compounds for pest control: insecticidal and acaricidal activity of essential oil components from heartwood of Alaska yellow cedar.
Laboratory bioassays were conducted to determine the activity of 15 natural products isolated from essential oil components extracted from the heartwood of Alaska yellow cedar, Chamaecyparis nootkatensis (D. Don) Spach., against Ixodes scapularis Say nymphs, Xenopsylla cheopis (Rothchild), and Aedes aegypti (L.) adults. Four of the compounds from the essential oil have been identified as monoterpenes, five as eremophilane sesquiterpenes, five as eremophilane sesquiterpene derivatives from valencene and nootkatone, and one as a sesquiterpene outside the eremophilane parent group. Carvacrol was the only monoterpene that demonstrated biocidal activity against ticks, fleas, and mosquitoes with LC50 values after 24 h of 0.0068, 0.0059, and 0.0051% (wt:vol), respectively. Nootkatone from Alaska yellow cedar was the most effective of the eremophilane sesquiterpenes against ticks (LC50 = 0.0029%), whereas the nootkatone grapefruit extract exhibited the greatest biocidal activity against fleas (LC50 = 0.0029%). Mosquitoes were most susceptible to one of the derivatives of valencene, valencene-13-aldehyde (LC50 = 0.0024%), after 24 h. Bioassays to determine residual activity of the most effective products were conducted at 1, 2, 4, and 6 wk after initial treatment. Residual LC50 values for nootkatone did not differ significantly at 4 wk posttreatment from the observations made at the initial 24-h treatment. The ability of these natural products to kill arthropods at relatively low concentrations represents an alternative to the use of synthetic pesticides for control of disease vectors.
Panella
Nicholas A
NA
Division of Vector-Borne Infectious Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Public Health Service, U.S. Department of Health and Human Services, Fort Collins, CO 80522, USA.
Dolan
Marc C
MC
Karchesy
Joseph J
JJ
Xiong
Yeping
Y
Peralta-Cruz
Javier
J
Khasawneh
Mohammad
M
Montenieri
John A
JA
Maupin
Gary O
GO
D000330:Aedes; D000818:Animals; D029780:Chamaecyparis / Q000737:chemistry*; D000081007:Cymenes; D007306:Insecticides; D018884:Ixodes; D039821:Monoterpenes; D009822:Oils, Volatile / Q000737:chemistry*; D010938:Plant Oils / Q000737:chemistry; D000081223:Polycyclic Sesquiterpenes; D012717:Sesquiterpenes; D005423:Siphonaptera; D013729:Terpenes; D014934:Wood
D000081007:Cymenes; D007306:Insecticides; D039821:Monoterpenes; D009822:Oils, Volatile; D010938:Plant Oils; D000081223:Polycyclic Sesquiterpenes; D012717:Sesquiterpenes; D013729:Terpenes; C073316:carvacrol; C050302:nootkatone