Chemical composition and insecticidal action of essential oil from Lantana montevidensis (Spreng.) Briq. (Chumbinho) against Nauphoeta cinerea

Resumen

Introduction: Among the botanical taxa that have species rich in essential oils, the Verbenaceae stands out. One species of this taxon, Lantana montevidensis (Spreng.) Briq., known as "chumbinho", is characterized by the presence of monoterpenes and sesquiterpenes, which together form the essential oils that have biological activities.

Objective: To identify the chemical constituents of L. montevidensis essential oil and to evaluate its insecticidal activity against Nauphoeta cinerea.

Methodology: L. montevidensis leaves were collected, dried and submitted to hydrodistillation, after which their chemical characterization was carried out by means of Gas Chromatography coupled to Mass Spectrometry (CG/MS). For the biological assay against cockroaches, nymphs with 20 days of age were submitted to different concentrations (50 - 1000 μg/mL of oil per air) and mortality was evaluated over 24 hours of EO exposure. As a positive control, ethanol (C₂H₆O) was used.

Results: The study shows that L. montevidensis oil has a low insecticidal action, since there was only 10% mortality in the 500 μg/mL group, while in the positive control there was a 95% mortality in the concentration of 500 μg/mL. As to the chemical composition of the oil, a total of 22 constituents were found, and it presented two major constituents: β-Caryophyllene (33.72%) and Germacreno D (31.98%).

Conclusion: Thus, the essential oil of L. montevidensis presents an insecticidal action and presents sesquiterpene compounds in its constitution.