Jatropha curcas L (Euphorbiaceae) como novo bioinseticida: analise fitoquimica preliminar e atividade larvicida contra Aedes aegypti (Diptera: Culicidae)

Abstract

Introduction: Dengue is a viral disease transmitted by the mosquito Aedes aegypti L. No vaccine has yet been validated, so there is a need to develop new products with new modes of action and cause less environmental impact. Objective: To evaluate the toxicity of Jatropha curcas against the larvae of A. aegypti and determine the preliminary phytochemical profile. Methods: The extracts of leaves and stem of J. curcas were macerated for seven days in 500 mL of 70% ethanol and using a rotary evaporator. The extracts were subjected to phytochemical screening and larvicidal activity. For the bioassay, the extracts in the concentration of 100μg/ml were suspended in disposable cups containing 100ml of distilled water and 15 larvae in 3rd stage of A. aegypti each cup. Data were analyzed using the statistical program SISVAR 4.8, with a significance level of p<0.05. Results: Phytochemical screening detected the presence of proteins and amino acids, and Depsides depsidonas, phenols and tannins, alkaloids, steroids and triterpenoids, saponins and polysaccharides in the extract from leaves and stems of J. curcas. The efficacy analysis of both extracts (leaf and stem) of J.curcas on A. aegypti showed significant insecticidal effect on the 3rd stage larvae of this mosquito and differed statistically with the control group at both assessment periods (** p <0.01). Conclusion: The results of this study contributed phytochemical information of this kind, but also the potential of this plant in controlling larvae of A. aegypti.