Acaricidal Activity of Tea Tree and Lemon Oil Nanoemulsions against Rhipicephalus annulatus

Abstract

Tick infestation is a serious problem in many countries since it has an impact on the health of animals used for food production and pets, and frequently affects humans. Therefore, the present study aimed to investigate the acaricidal effects of nanoemulsions of essential oils of Melaleuca alternifolia (tea tree, TT) and Citrus limon (lemon oil, CL) against the different stages (adult, eggs, and larvae) of deltamethrin-resistant Rhipicephalus annulatus ticks. Three forms of these oils were tested: pure oils, nanoemulsions, and a binary combination. Tea tree and lemon oil nanoemulsions were prepared, and their properties were assessed using a zeta droplet size measurement and a UV-Vis spectrophotometer. The results showed that TT and CL exhibited higher adulticidal effects in their pure forms than in their nanoemulsion forms, as demonstrated by the lower concentrations required to achieve LC50 (2.05 and 1.26%, vs. 12.8 and 11.4%, respectively) and LC90 (4.01% and 2.62%, vs. 20.8 and 19.9%, respectively). Significant larvicidal activity was induced by the TTCL combination, and LC50 was reached at a lower concentration (0.79%) than that required for the pure and nanoemulsion forms. The use of pure CL oil was found to have the most effective ovicidal effects. In conclusion, pure TT and CL have potent acaricidal effects against phenotypically resistant R. annulatus isolates. It is interesting that the activity levels of TT and CL EOs’ binary and nanoemulsion forms were lower than those of their individual pure forms.

Termiticidal, biochemical, and morpho-histological effects of botanical based nanoemulsion against a subterranean termite, Odontotermes Formosanus Shiraki

“…The formation of E-NE and N-NE was confirmed through UV–Vis spectrophotometry, showing strong absorption peaks at 290 nm and 285 nm, respectively. The same range in UV absorbance was reported in previous studies of other nanoemulsions of essential oils, for instance, Melaleuca alternifolia (Maiden & Betche) Cheel ( M. alternifolia ) ( Ibrahium et al., 2022 ), Ocimum basilicum L. ( O. basilicum ), and Cuminum cyminum L. ( C. cyminum ) ( Abdelaal et al., 2021 ). Our findings show that E-NE and N-NE have small particle sizes and PdI values below 0.04, which show that the NE droplets are monodispersed, have a limited size distribution, and have good long-term stability ( Barik and Singh, 2019 ).…”

“…Conductivity is the ability of any molecule to transfer electricity between two points (Talegaonkar et al, 2011). Ibrahium et al (2022), recorded that nanoemulsions of M. alternifolia and Citrus limon (L.) Osbeck have mean droplet sizes of approximately 188.4 d.nm and 50.66 d.nm with PDI values of 0.527 and 0.171, respectively, and a Z-average of -2.02 mV and -2.30 mV, respectively. Clerici et al (2018), detected DLS for E. globulus nanoemulsion was 79.80 ± 0.37 nm with a PDI value of 0.21 ± 0.007.…”

“…Several techniques were used to characterize E-NE and N-NE according to the method of Ibrahium et al. (2022) , with a few modifications.…”

“…Several techniques were used to characterize E-NE and N-NE according to the method of Ibrahium et al (2022), with a few modifications. The surface plasma resonance of E-NE and N-NE was measured by ultraviolet using UV-Vis spectrophotometry (Shimadzu Corporation, Kyoto, Japan) in the range of 200-800 nm.…”

The acaricidal and repellent activity of the essential and nano essential oil of Thymus vulgaris against the brown dog tick, Rhipicephalus sanguineus (Acari: Ixodidae)

“…In line with our results, nanostructured forms of Eucalyptus globulus was not effective on the reproduction of Rhipicephalus microplus [34]. Similar data reported after using Tea tree and lemon nano oils on adult female of R. annulatus [35] and nano EO of Cinnamomum verum on R. microplus [36]. In contrast, geranium oil nanoemulsion displayed greater impact on R. annulatus, compared to the pure form [37].…”