Fumigant and Repellent Properties of Essential Oils and Component Compounds Against Permethrin-Resistant <I>Pediculus humanus capitis</I> (Anoplura: Pediculidae) from Argentina

Abstract

The repeated use of permethrin and other insecticides for the control of head lice, Pediculus humanus capitis De Geer (Anoplura: Pediculidae), during past decades has resulted in the development of marked levels of resistance. Thus, new alternative insecticides are needed for the control of head lice. We studied the fumigant and repellent properties of essential oils from 16 native and exotic plants in Argentina, and 21 chemical components against permethrin-resistant head lice from Argentina. With a direct vapor-exposure bioassay, the most effective oil was from the native Myrcianthes cisplatensis Cambess (Myrtaceae) with a time to 50% knockdown (KT50) of 1.3 min, followed by exotic species, Eucalyptus cinerea F.V. Muell., Eucalyptus viminalis Labill., and Eucalyptus saligna Smith. with KT50 values of 12.0, 14.9, and 17.4 min, respectively. The most effective components were 1,8-cineole and anisole, with KT50 values of 11.1 and 12.7 min, respectively. Regression analysis of KT50 values and vapor pressures and water-partition coefficients for the essential oil components revealed that the most effective fumigants were among the more volatile components. Repellency assays indicated that the essential oil from Mentha pulegium L. and its benzyl alcohol component were the most effective repellents, having repellency indices of 75.5 and 57.8%, respectively. Thus, some Argentinean plants contain essential oils and components that function as fumigants or as repellents and thereby show potential for development of new control products for head lice.

Evaluation of the Insecticidal Activities of Three Eucalyptus Species Cultivated in Iran, Against Hyphantria Cunea Drury (Lepidoptera: Arctiidae)

“…These 20 have been commercially used for the production of essential oils in the pharmaceutical and cosmetic industries (Pino et al 2002). Furthermore, previous studies have shown that, in general, the toxicity of plant essential oils against insect pests is related to their major components such as 1,8-cineole (Choi et al 2006;Toloza et al 2006;Alzogaray et al 2011;Akhtar et al 2012).…”

“…These oils are often responsible for a plants distinctive scent or taste. Essential oils have a rather complex composition, with component compounds generally consisting of low-molecular-weight monoterpenes (10-carbon) and related phenols (Toloza et al 2006). The main characteristics of the essential oils are that they are easily extractable, ecofriendly, biodegradable, possess low or no toxicity against mammals, and are very effective against a wide spectra of insect pests (Lucia et al 2012).…”

CHEMICAL COMPOSITION, ANTIMICROBIAL, ANTIOXIDANT AND CYTOTOXIC ACTIVITIES OF <i>EUCALYPTUS CHAPMANIANA</i> GROWN IN IRAQ

“…Eucalyptol was also found in majority of other species of Eucalyptus, such as E. staigeriana (Gilles et al, 2010), E. globules (Maciel et al, 2010;Tyagi and Malik, 2011) and E. urophylla (Cheng et al, 2009). Nevertheless, the main component in other species of Eucalyptus can be a different compound, such as piperitone (E. dives), (E)-methyl cinnamate (E. olida) (Gilles et al, 2010), α-pinene (E. camaldulensis) (Cheng et al, 2009), limonene (E. staigeriana), β-citronellal (E. citriodora) (Maciel et al, 2010), or p-cymene (E. tereticorni) (Toloza et al, 2006). The chemical composition of essential oil is affected by several factors, such as species, geographical location, harvest time, plant part and isolation method (Cimanga et al, 2002;Penalver et al, 2005;Marzoug et al, 2011).…”

Odorant receptor-based discovery of natural repellents of human lice

“…Since then, a wide range of molecules with repellent activities, including natural substances derived from plants as well as synthetics have been developed (Peock and Maunder, 1993) (Burgess, 1993) (Mumcuoglu et al, 1996) (Mumcuoglu et al, 2004) (Toloza et al, 2006a) (Toloza et al, 2006b) (Toloza et al, 2008) (Canyon and Speare, 2007) (Semmler et al, 2010), but nothing was known regarding their mode of action at the insect level. The results of our study indicate that PhumOR2 is linked to avoidance behavior by mediating the reception of natural repellents.…”

“…Several types of repellent products have been considered for louse control, including broad-spectrum synthetics such as N,N-diethyl-3-methylbenzamide (DEET) and plant-derived compounds such as essential oils and some of their constituents (e.g. citronellal) (Peock and Maunder, 1993) (Burgess, 1993) (Mumcuoglu et al, 1996) (Mumcuoglu et al, 2004) (Toloza et al, 2006a) (Toloza et al, 2006b) (Toloza et al, 2008) (Canyon and Speare, 2007) (Semmler et al, 2010). Nevertheless, no specific anti-louse repellent has been discovered to date (Semmler et al, 2012) (Burgess et al, 2014).…”