Abstract
Carvacrol is a monoterpenoid phenol found in many essential oils that has antibacterial, antifungal and antiparasitic activities. Drug loaded-invasome systems are used to deliver drugs utilizing nanoparticles to improve bioavailability, efficacy, and drug release duration. As a result, the present study developed carvacrol-loaded invasomes and evaluated their acaricidal effect against
Rhipicephalus annulatus
(cattle tick) and
Rhipicephalus sanguineus
(dog tick). Carvacrol loaded-invasome (CLI) was prepared and characterized using UV/Vis spectrophotometer, zeta potential measurements, Scanning Transmission Electron Microscopy (STEM), Fourier Transform Infrared (FT-IR) Spectroscopy, and Differential Scanning Calorimetry Analysis. CLI (5%) induced significant mortality (100%) in
R. annulatus
adult ticks with LC
50
of 2.60%, whereas the LC
50
of pure carvacrol was 4.30%. Carvacrol and CLI were shown to have a significant larvicidal action on both tick species, with LC
50
s of 0.24 and 0.21% against
R. annulatus
and 0.27 and 0.23% against
R. sanguineus
, respectively. Carvacrol and CLI (5%) induced significant repellent activities for 24 h against
R. annulatus
and
R. sanguineus
, as evidenced by the rod method and the petri-dish selective area choice method, respectively. High-performance liquid chromatography (HPLC) demonstrated that the CLI form had 3.86 times the permeability of pure carvacrol. Moreover, carvacrol and CLI inhibited acetylcholinesterase activity and decreased glutathione and malonedealdehyde levels in the treated ticks. In conclusion, invasomes significantly improved adulticidal and repellency activities of carvacrol against both tick species.