512-1 | N-BENZYL-SUBSTITUTED IMIDAZOLIUM SALT IN THE VECTORAL CONTROL OF AEDES AEGYPTI | Autores: Clarissa Martins Leal Schrekker (UFRGS - UNIVERSIDADE FEDERAL DO RIO GRANDE DO SUL ) ; Igor Luiz Gonçalves Pereira (UFRGS - UNIVERSIDADE FEDERAL DO RIO GRANDE DO SUL ) ; Henri Stephan Schrekker (UFRGS - UNIVERSIDADE FEDERAL DO RIO GRANDE DO SUL ) ; Onilda Santos da Silva (UFRGS - UNIVERSIDADE FEDERAL DO RIO GRANDE DO SUL ) |
Resumo: The main arboviruses such as Dengue, Zika and Chikungunya are transmitted by mosquitoes of the genus Aedes, mainly Ae. aegypti and Ae. albopictus. The most effective control strategy to prevent arboviruses is vector control of transmitting mosquitoes. Imidazolium salts (IS) are substances that have various chemical and pharmaceutical applications, due to their physical and chemical properties, presenting several biological activities. This study aims to investigate the effects of a N-benzyl-substituted IS (NbIS) in Ae. aegypti and to develop an effective formulation for biological control of the mosquito. For the bioassays, populations of Rockefeller strain Ae. aegypti were kept in the laboratory at 25 ± 2 °C, photoperiod of 12h light and 12h dark and relative humidity of approximately 80% in germination chambers. For the continuous population of mosquitoes, the larvae, after emerging, were kept in trays with filtered water in the germinators. The pupae were removed daily and relocated in another container until the adult stage, and adults were kept in cages. The source of carbohydrates for the adults was an aqueous solution with honey and the blood meal for the females was performed with the blood of laboratory mice. Females performed oviposition every two days after the blood meal. To carry out the bioassays, 600 third and fourth instar larvae of Ae. aegypti were exposed to six different concentrations (10, 5, 2.5, 1.25, 0.625 and 0.3125 μg/mL) of the NbIS. In each flask, 25 larvae, filtered water and the IS solution were added. As the positive control, the IS C18MImCl was used at a concentration of 40 μg/mL, 25 larvae and filtered water. In the negative control, 25 larvae and filtered water were used. Starting from the stock solution, serial dilutions were performed. The flasks were placed in germination chambers, photoperiod of 12h light and 12h dark and relative air humidity of 80%, at 28 °C. Larval mortality was determined at 24h and 48h. The bioassays were performed in triplicate, four times in different periods. Through the results obtained; it was possible to verify that NbIS presented the highest lethality rates in Ae. aegypti larvae in concentrations of 10, 5 and 2.5 μg/mL in 24h and 48h. At a concentration of 10 μg/mL, the highest lethality for larvae (100%) was obtained in 24h and 48h. At concentrations of 5 μg/mL and 2.5 μg/mL, the lethality was approximately 100% in 24h and 48h. The sub-lethal concentrations were at 1.25, 0.625 and 0.3125 μg/mL. Analyzes were carried out to verify whether this IS continued to present lethality in the larvae for a longer period at 72h, 96h and 144h. It was found that NbIS continued to act on the larvae at 72h, 96h and 144h, with high lethality (100%) at concentrations of 10, 5, 2.5 and 1.25 μg/mL, and sub-lethal doses at concentrations of 0.625 μg/mL and 0.3125 μg/mL, showing prolonged lethality in Ae. aegypti larvae. Thus, it appears that the NbIS is a compound with great potential to be used in new technologies for the eradication of arboviruses caused by Ae. aegypti.
Keywords: Imidazolium salt, Arboviruses, Ae. aegypti.
Development Agency: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES). Palavras-chave: Imidazolium salt, Arboviruses, Ae. aegypti
Agência de fomento: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES). |