Avaliação de clorofilina cúprica de sódio como agente fotossensibilizador para o controle de Aedes aegypti (Diptera: Culicidae)

Abstract

Yellow fever, dengue, chikungunya and zika are viral diseases with an increased risk of public health damage. These diseases are transmitted by Aedes aegypti mosquitoes. Control of eggs (egg bank of broodstock), larvae and adult insects (winged) is crucial for containment and/or prevention of outbreaks of these diseases, especially in hot and humid periods. The discovery of new larvicides can make population control more efficient and with less environmental impact, especially if we use approaches that consider the behavior and ecology of the insect vector. Porphyrins and their conjugated structures are classes of molecules that absorb light and can generate reactive oxygen species which, if excited by ultraviolet and / or visible light, can induce continuous cellular damage by oxidation and cell death from the insect digestive system. The present work evaluates the cytotoxic activity induced by solar radiation and/or artificial light for the control of A. aegypti larvae, besides evaluating the toxicity, cytotoxicity, genotoxicity and mutagenicity in meristematic cells of Allium cepa roots. The sodium cupric chlorophyllin was used as a photosensitizer. The experimental results showed mortality in larvae of A. aegypti of 3rd and 4th larval stages at concentrations of 15 to 35 mg L-1 on exposure to direct solar irradiation during five hours with sunlight intensity ranging from 52.27 W m -2 to 128.7 W m-2. The sodium cuprous chlorophyll in the concentration between 50 and 200 mg L-1 showed no toxicity, cytotoxicity, genotoxicity, mutagenicity, and potentiated the cell division in all evaluated concentrations. The study opens perspectives for the development of new strategies and more sensitive molecules for radiation intensities lower than typical values and obtained from sunlight. The production of free radical and / or oxidant species can kill insects due to damage to the tissues of the digestive and intestinal system, as well as adsorb in organic material from the breeding sites, control the insect via the food chain and/or maintain activity Playback cycles. The results showed that sodium cuprous chlorophyllin is photosensitizing and a promising agent for photodynamic control for adult larvae and insects of the dengue mosquito, and possibly for other insects of similar reproductive cycle.