Acaricidal and larvicidal activity of leaves and fractions of rose pepper (Schinus terebinthifolius Raddi. (Anacardiaceae) essential oil against Rhipicephalus (Boophilus) microplus

Abstract

This experiment aimed to investigate the chemical composition and the acaricidal and larvicidal activities of essential oil (EO) and fractions from rose pepper (Schinus terebinthifolius (Raddi) leaves against Rhipicephalus (Boophilus) microplus. The EO was obtained from fresh leaves of adult rose pepper specimens by hydrodistillation (2h), then fractioned by column chromatography and analyzed by gas chromatography coupled to mass spectrometry (GC/MS). The acaricidal activity was determined by Adult Immersion Test (AIT) and Larval Packet Test (LPT). The concentrations of EO for AIT were from 500.00 to 0.19 mg/mL, and for LPT were from 12.50 to 0.00018 mg/mL. The mortality percentage (%) of female and larvae ticks were obtained by calculating the average ± standard error utilizing the Microsoft Excel® program. The data were submitted to analysis of variance (ANOVA) and compared utilizing Sisvar 5.6 program by Scott-Knott's test (p<0.05). The values of lethal concentration (LC 50 and LC 99.9) and their respective confidence intervals (CI) were calculated by Probit analysis. Bioassays showed that EO from leaves killed 40.00% of the females and inhibited 97.06% of egg hatchability at the dose of 500.00 mg/mL, and high activity on larvae, presenting LC 50 0.0026 ± 0.0004 mg/mL and LC 99.9 of 8.58 ± 0.03 mg/mL. The probable action mechanism of EO and fractions was established by the bioautographic method, measuring the inhibition potential on the acetylcholinesterase enzyme, indicating an inhibition until the concentration of 0.0003 mg/mL. These results allow new perspectives to propose new biomolecules as a way to minimize tick resistance against conventional acaricides.

Controle de carrapato bovino (Rhipicephalus microplus) com óleo essencial de folhas de Psidium rufum DC

“…Rhipicephalus microplus Canestrini (Acari: Ixodidae) is an ectoparasite with 21-day parasitic life cycle in live host and its free-living stage is up to 300 days in pastures without live host (Medeiros et al, 2019). This tick is responsible for the transmission of hemotozoas such as Babesia bovis, Babesia bigemina, and Anaplasma marginata, which cause diseases and may lead to animal death (Bortolucci et al, 2018;Cazella et al, 2020). The tick can cause anemia, mass reduction, milk production Research, Society and Development, v. 9, n. 11, e409119550, 2020 (CC BY 4.0) | ISSN 2525-3409 | DOI: http://dx.doi.org/10.33448/rsd-v9i11.9550 reduction, birth rate reduction, increase in mortality rates, labor and material costs, mainly for the treatment of bovine parasite sadness, in addition to reducing bovine leather due to the animal's inflammatory response to the ectoparasite (Sugauara et al, 2019;Pires Filho et al, 2020).…”