Laboratory assessment of the acaricidal, repellent and anti-cholinesterase effects of Melaleuca alternifolia and Chamaemelum nobile essential oils against Hyalomma scupense ticks

Dhouha Alimi; Najla Trabelsi; Azhar Hajri; Marwa Ben Amor; Asma Mejri; Selim Jallouli; Hichem Sebai

doi:10.1007/s11259-024-10313-3

Laboratory assessment of the acaricidal, repellent and anti-cholinesterase effects of Melaleuca alternifolia and Chamaemelum nobile essential oils against Hyalomma scupense ticks

Vet Res Commun. 2024 Jan 25. doi: 10.1007/s11259-024-10313-3. Online ahead of print.

Authors

Dhouha Alimi¹, Najla Trabelsi², Azhar Hajri³, Marwa Ben Amor², Asma Mejri², Selim Jallouli⁴, Hichem Sebai³

Affiliations

¹ Laboratory of Functional Physiology and Valorization of Bio-Resources (LR23ES08), Higher Institute of Biotechnology of Beja, University of Jendouba, Habib Bourguiba Street, Box 382, 9000, Beja, Tunisia. dhouha.enmv@gmail.com.
² Laboratory of Olive Biotechnology, Center of Biotechnology of Borj-Cedria, Hammam-Lif, Tunisia.
³ Laboratory of Functional Physiology and Valorization of Bio-Resources (LR23ES08), Higher Institute of Biotechnology of Beja, University of Jendouba, Habib Bourguiba Street, Box 382, 9000, Beja, Tunisia.
⁴ Laboratory of Bioactive Substances, Centre of Biotechnology of Borj-Cedria, Box 901, 2050, Hammam-Lif, Tunisia.

PMID: 38267710
DOI: 10.1007/s11259-024-10313-3

Abstract

In cattle, Hyalomma scupense serves as an important vector of several pathogens resulting in diseases, subsequently affecting the agricultural field as well as the economy. Resistance to chemical acaricides has become widespread affirming the need for new drugs to tick control. The goal of this study was to investigate the acaricidal, repellent activities as well as the putative mode of action of two essential oils (EOs) from Melaleuca alternifolia (Tea tree) and Chamaemelum nobile (Roman chamomile) on Hyalomma scupense. The chemical composition of EOs was also evaluated. Different concentrations of EOs were tested in vitro for their acaricidal property on adults and larvae of H. scupense using adult immersion test (AIT) and larval packet test (LPT). Additionally, using Ellman's spectrophotometric method, the anticholinesterase (AChE) inhibition activity of M. alternifolia and C. nobile EOs was assessed in order to understand their putative mode of action. The main compounds of C. nobile were α-Bisabolene (22.20%) and (E)-β-Famesene (20.41%). The major components in the analyzed M. alternifolia were Terpinen-4-ol (36.32%) and γ-Terpinene (13.69%). Adulticidal and larvicidal assays demonstrated a promising efficacy of the essential oils against tick H. scupense. The lethal concentration (LC₅₀) values obtained for M. alternifolia and C. nobile oils were 0.84 and 0.96 mg/mL in the AIT and 0.37 and 0.48 mg/mL in the LPT, respectively. Regarding repellent activity, M. alternifolia achieved 100% repellency at the concentration of 1 mg/mL while C. nobile showed 95.98% repellency activity at concentration of 4 mg/mL. Also, M. alternifolia and C. nobile EOs displayed potent AChE inhibition with IC₅₀ value of 91.27 and 100.12 μg/mL, respectively. In the present study, M. alternifolia and, to a lesser degree, C. nobile EOs were found to be effective in vitro acaricides, repellents and acetylcholinesterase inhibitor against H. scupense ticks. These plants may represent an economical and sustainable alternative to toxic synthetic acaricides in the management of ectoparasites of veterinary importance.

Keywords: Acaricidal; Acetylcholinesterase; Chamaemelum nobile; Hyalomma scupence; Melaleuca alternifolia; Repellent.