Antioxidant and Toxiciy Studies of Two Acaricidal Plants, Cymbopogon citratus and Eucalyptus globulus

Abstract

Background: The menace of acaricide resistance, which confronts animal owners with attendant losses, and the issue of safety with commercially available acaricides are enormous, hence the search for alternatives. Objectives: This study evaluated the safety profile of essential oils (EOs) of two acaricidal plants with proven efficacy against ticks. Methods: EOs from Cymbopogon citratus and Eucalyptus globulus were extracted by hydrodistillation, while acute, subacute oral, and dermal toxicities of the plants and their combination were evaluated in vivo using Wistar rats according to a procedure described by the Organization for Economic Cooperation and Development (OECD) guidelines. Thereafter, blood samples were collected for complete blood counts, serum biochemistry, antioxidant properties, and reproductive hormonal profiles, and tissues were harvested for histopathology. Data were analyzed using SPSS software, version 20, and analysis of variance (ANOVA) was conducted, with P≤0.05 considered statistically significant. Results: The packed cell volume (PCV) for C. citratus (55±1.05%) and E. globulus (55.6±0.93%) was higher (P<0.05) than that of the control group (47.2±2.50%). Serum creatinine was significantly higher in all the test groups than in the control group (P<0.05). Progesterone, luteinizing hormone, and follicle-stimulating hormone levels were significantly lower, while estrogen levels were higher in the test groups compared to the control. Histopathology revealed normal hepatocytes, with mild distension of Bowman’s capsule in the kidney at doses much higher than those required for acaricidal efficacy. Conclusion: C. citratus and E. globulus EO combination has the potential to be developed into an environmentally friendly botanical acaricide.