Evaluation of Essential Oils from the Brazilian Species Baccharis trimera (Less.) DC. and Mimosa verrucosa Benth. against Ctenocephalides felis felis Bouché

Essential oils (EO) have the potential to control ectoparasites, being an alternative to the use of synthetic products. The essential oils of Baccharis trimera and Mimosa verrucosa were evaluated for lethality, residual efficacy, and repellence against the ectoparasite Ctenocephalides felis felis Bouché, and toxicity was using Saccharomyces cerevisiae eukaryote model. EOs were obtained by steam distillation and characterized by GC/FID/MS. Mortality at different immature stages and among adult fleas was measured through in vitro filter paper tests at different concentrations of EOs, as well as residual effect and repellent activity. The major compounds for B. trimera were carquejyl acetate (33.0%), carquejol (7.07%), and palustrol (6.99%), and for M. verrucosa, β-pinene (14.2%), (E)-caryophyllene (13.8%), and α-pinene (10.6%). Low toxicity was recorded for B. trimera and M. verrucosa EOs at 200 µg.mL^-1. EOs recorded 100% efficacy against adult fleas at 800 µg.cm^-2 (LC₅₀ = 369.22 µg.cm^-2) and residual effect for three days, B. trimera EO promoted 46.7% of mortality on the 3^rd day of the exposition, and M. verrucosa EO 20% of mortality on the 3^rd day of the exposition. The repellent activity was presented in the concentration of 40000 µg.mL^-1 for B. trimera EO (80% at 12h) and M. verrucosa EO (75% at 6h). The results show great potential for developing alternative products from the essentials of B. trimera and M. verrucosa in control against C. felis felis, which show low toxicity and high activity.

Keywords:
volatile oil; biocontrol; biopesticide; fleas; toxicity.

Essential oils rich in terpene compounds.

Baccharis. trimera has pulicidal potential against adult fleas

Mimosa verrucosa has pulicidal potential against larvae and adult fleas.

Essential oils have repellent activity.