Toxicological Stability of Ocimum basilicum Essential Oil and Its Major Components in the Control of Sitophilus zeamais

Abstract

Essential oils (EOs) are widely recognized as efficient and safe alternatives for controlling pest insects in foods. However, there is a lack of studies evaluating the toxicological stability of botanical insecticides in stored grains in order to establish criteria of use and ensure your efficiency. The objective of this work was to evaluate the toxicological stability of basil essential oil (O. basilicum) and its linalool and estragole components for Sitophilus zeamais (Motschulsky) adults in corn grains by fumigation. The identification of the chemical compounds of the essential oil was performed with a gas chromatograph coupled to a mass selective detector. Mortality of insects was assessed after 24 h exposure. After storage for six (EO) and two months (linalool and estragole) under different conditions of temperature (5, 20, and 35 °C) and light (with and without exposure to light), its toxicological stability was evaluated. Studies revealed that the essential oil of O. basilicum and its main components exhibited insecticidal potential against adults of S. zeamais. For greater toxicological stability, suitable storage conditions for them include absence of light and temperatures equal to or less than 20 °C.

Composition, Antibacterial Efficacy, and Anticancer Activity of Essential Oil Extracted from Psidium guajava (L.) Leaves

“…A gas chromatograph–mass spectrometer model QP2010 (Shimadzu, Tokyo, Japan) equipped with an autosampler and autoinjector (AOC-20si) was used for this study. The procedures for injection, separation, and identification of compounds, as well as the temperature of the column oven, were based on previous reports with some modifications [ 58 , 59 ]. The essential oil was dissolved in hexane (10 mg/mL), and the system was operated at 70 eV.…”

Encapsulation of Rosmarinus officinalis essential oil and of its main components in cyclodextrin: application to the control of the date moth Ectomyelois ceratoniae (Pyralidae)

“…The LC 50 values at 15 °C were estimated as 19.3, 16.9 and 27.1 μL L −1 air and were estimated at 30 °C as 24.4, 33.9 and 27.1 μL L −1 air, respectively, for the EO, thymol and carvacrol. Furthermore, Moura et al 42 displayed that light affects negatively the stability of Ocimum basilicum EO and decreases the toxicity against Sitophilus zeamais population. Numerous modern technological innovations involving different delivery systems have been explored to reduce these defects.…”

A review of insecticidal effect of essential oils on stored grain pests

“…basilicum is mainly composed of linalool and estragole, its toxicity can be explained by the action of the mixed activity of the enzyme acetylcholinesterase (AChE), especially when they are applied by fumigation. Namely, a study on corn grains showed that the increase in temperature (35 °C) and exposure to light during processing affected the stability of this EO (Moura et al, 2021).…”