Dados do Trabalho

Título

Eco-friendly activity of essential oil from Tetradenia riparia (Hochstetter.) Codd (Lamiaceae) and fenchone against Anopheles and Aedes larvae

Introdução

In Brasil malaria and dengue are diseases transmitted by Anopheles darlingi and Aedes aegypti mosquitoes resistant to synthetic commercial insecticides, which in turn are toxic products for non-target animals. On the other hand, alternative ecologically correct control strategies are being focused on natural products extracted from Amazonian plants.

Objetivo(s)

In this aspect, the aim of the study was to investigate the toxicity of essential oil (EO) from Tetradenia riparia (Lamiaceae) and fenchone against malaria and dengue vectors, as also against non-target animals. In addition, the mechanism of action of EO and fenchone was investigated.

Material e Métodos

The EO from T. riparia was extracted by hydrodistillation and characterized by gas chromatography–based approaches, being its toxicity, along with a fenchone, evaluated against An. darlingi, An. albitarsis, An. triannulatus, An. nuneztovari, Ae. aegypti and Ae. albopictus (Culicidae), as well as against Toxorhynchites haemorrhoidalis (Culicidae) and Gambusia affinis (Poeciliidae). In addition, their acetylcholinesterase (AChE) activities were evaluated.

Resultados e Conclusão

The EO of T. riparia yield 1.4 ± 0.17% and presented fenchone (31.62%) as the main constituent. Moreover, the EO showed significant larvicidal activity against Anopheles (LC50 from 30.21 to 35.21 ppm) and Aedes (LC50 from 29.31 to 40.76 ppm). On the other hand, fenchone showed higher larvicidal activity against Anopheles (LC50 from 5.93 to 6.86 ppm) and Aedes (LC50 from 3.65 to 7.00 ppm) than EO. Furthermore, the EO and fenchone presented significant inhibition of AChE (IC50 from 1.93 to 2.65 ppm). Regarding the toxicity, α-cypermethrin (positive control) was extremally toxic against T. haemorrhoidalis and G. affinis (LC50 of 0.22 to 0.29 ppm) (IS/FSP from 1.04 to 2.23) than the EO and fenchone that presented low toxicity (LC50 of 22.38 to 357.17 ppm) (IS/FSP from 2.59 to 12.18). Thus, the present study demonstrated that EO of T. riparia and its main constituent fenchone could be an alternative ecologic to control malaria and dengue vectors.

Palavras-chave

Amazonian, Anopheles, Aedes, Lamiaceae, biological control.