Efeito tóxico do composto 2-feniletinil-butiltelúrio sobre a mosca da fruta Drosophila melanogaster: possível ação inseticida

Abstract

The inappropriate use of insecticides has caused a variety of environmental problems and damages to human health along the years, leading to a search for non-harmful alternative products. PEBT is an organic tellurium compound that has shown to be promising, as it is not toxic to mammals, however it can be to other species, like bacteria, which raises the question about its possible insecticidal action. The fruit fly (Drosophila melanogaster) is considered as a reference model in scientific research and it has been used, among other things, to test the toxicity of some insecticides. In this context, the objective of the present study is to evaluate the insecticide potential of 2-phenylethynyl-butyltellurium, in different concentrations, on the fruit fly (Drosophila melanogaster). The experiment was conducted in the Pharmacological and Toxicological Evaluations Applied to Bioactive Molecules Laboratory (LaftambioPampa) in the Federal University of Pampa, Itaqui, RS. The treatments consisted of four groups, a control group [1] and three different concentrations of PEBT: 0, 325 mM [2], 1,3 mM [3], e 5,2 mM [4]. There were used 150 flies for each group, with 3 repetitions. The evaluations consisted on an open field assay and a negative geotaxia of flies test (In vivo), mortality rate and acetylcholinesterase (AChE) activity (Ex vivo). The toxic effect of PEBT on Drosophila melanogaster and its possible insecticidal action were verified, and the lethal median concentration was determined as 2,386 mM, in 48h. In all the concentrations, PEBT reduced the locomotor and exploratory behavior of the fly, in 24 and 48 hours. Its toxicity is not due to the inhibition of the acetylcholinesterase (AChE) activity, but possibly to its pro oxidant effects which induce the oxidative stress in the flies.