Fumigant Activity of the Psidium guajava Var. Pomifera (Myrtaceae) Essential Oil in Drosophila melanogaster by Means of Oxidative Stress

The guava fruit,Psidium guajavavar. pomifera (Myrtaceae family), is a native plant from South America. Its leaves and fruits are widely used in popular medicine in tropical and subtropical countries.Drosophila melanogasterhas been used as one of the main model organisms in genetic studies since the 1900s. The extensive knowledge about this species makes it one of the most suitable organisms to study many aspects of toxic compound effects. Due to the lack of studies on the effects of the bioactive compounds present in theP. guajavavar. pomifera essential oil, we performed a phytochemical characterization by CG-MS and evaluated the toxicity induced by the essential oil in theD. melanogasterinsect model. In order to understand the biochemical mechanisms of toxicity, changes on the Nrf2 signaling as well as hallmarks of oxidative stress response were followed in the exposed flies. Our results showed that exposure of insects to theP. guajavaoil increased mortality and locomotor deficits in parallel with an oxidative stress response signaling. Therefore, it suggested a bioinsecticidal activity forP. guajavavolatile compounds by means of oxidative stress. Further studies are ongoing to identify which oil compounds are responsible for such effect.