Repellent Activity of Fractioned Compounds fromChamaecyparis nootkatensisEssential Oil Against NymphalIxodes scapularis(Acari: Ixodidae)

Abstract

Preliminary repellent activity of 14 natural products isolated from essential oil components extracted from the heartwood of Alaska yellow cedar, Chamaecyparis nootkatensis (D. Don) Spach., were evaluated against nymphal Ixodes scapularis Say in a laboratory bioassay and compared with technical grade N,N-diethyl-3-methylbenzamide (deet). Four hours after treatment, nootkatone and valencene-13-ol had repellent concentration (RC)50 values of 0.0458 and 0.0712% (wt:vol), respectively; two additional Alaska yellow cedar compounds, nootkatone 1 --> 10 epoxide and carvacrol had reported RC50 values of 0.0858 and 0.112%, respectively. The observed RC50 value for deet was 0.0728% (wt:vol). Although not statistically significantly more active than deet, the ability of these natural products to repel ticks at relatively low concentrations may represent a potential alternative to synthetic commercial repellents.

In vitro effect of seven essential oils on the reproduction of the cattle tick Rhipicephalus microplus

“…Carrol et al [22] reported repellent action of juniper oil against two species of ticks ( Amblyomma americanum and Ixodes scapularis ). Studies conducted by Dietrich et al [23] and Dolan et al [24] have reported that the J. communis oil is a rich source of anti-tick compounds with well-known repellent and insecticidal activities. Researchers also found 43.2% of repellent effect for juniper oil against A. aegypti after 210 min of application [25].…”

Biological screening of selected Pacific Northwest forest plants using the brine shrimp (Artemia salina) toxicity bioassay

“…Tissues identified with LC 50 < 100 µg/ml cytotoxicity have served us as leads for further studies of bioactive extracts and compounds from heartwoods of yellow, incense, and Port-Orford cedars, and western juniper against mosquitoes ( Aedes aegypti ), ticks ( Ixodes scapularis ), fleas ( Xenopsylla cheopis ) or microbes influencing animal and forest health (Johnston et al 2001 ; Panella et al 2005 ; Dietrich et al 2006 ; Manter et al 2006 , 2007 ; Dolan et al 2007 , 2009 ). It is worthwhile noting that three of the compounds in yellow or incense cedar heartwoods have different modes of action than other commercially available mosquito adulticides currently in use (McAllister and Adams 2010 ).…”

Bioassays to evaluate non-contact spatial repellency, contact irritancy, and acute toxicity of permethrin-treated clothing against nymphal Ixodes scapularis ticks

“…In this assay, non-contact spatial repellency would be displayed by ticks approaching but not making physical contact with the treated textile, whereas contact irritancy would be displayed by ticks moving onto the treated textile but then becoming visibly agitated and retreating to the normal finger surface below the treated textile or dislodging from the textile and tumbling off the finger completely. However, initial trials with non-treated cotton textile (JoAnn Fabric #1491315) revealed that, despite their strong natural tendency to move upwards along a vertical surface when seeking a host (Dietrich et al, 2006), ticks were reluctant to leave the skin surface used as the introduction zone and move upward onto the test textile. Out of 50 I. scapularis nymphs (OSU) that climbed onto the tip of the finger in this assay, only 12 (24%) moved upward onto the non-treated test textile within a 5-min observation period and only 1 tick crossed the textile to reach the skin surface above.…”