Larvicidal activity against Aedes aegypti of pacharin from Bauhinia acuruana
Autor(es): Gois, Roberto Wagner da Silva; Sousa, Leoncio Mesquita de;Santiago, Gilvandete Maria Pinheiro; Romero, Nirla Rodrigues;Lemos, Telma Leda Gomes; Arriaga, Angela Martha Campos;Braz-Filho, Raimundo
Resumo: The aim of the present study was to evaluate the activity of pacharin isolated from the ethanol extract from roots of Bauhinia acuruana on third-instar larvae of Aedes aegypti Linn. (Diptera: Culicidae). The crude ethanol extract showed larvicidal activity at the concentration of 500 mu g/mL. Given this larvicidal activity, this extract was submitted to chromatographic fractionation on a silica gel column eluted with n-hexane, dichloromethane, ethyl ether, ethyl acetate, and methanol in order to isolate the active compound(s). Pacharin, obtained in pure form from fraction eluted with ethyl ether, was evaluated for their larvicidal effects against A. aegypti. In these bioassays, the larvae were exposed at concentrations of 500, 250, 100, 50, and 25 mu g/mL of the crude ethanol extract or pacharin. After 24 h, the number of dead larvae was counted and the LC50 values for larval mortality were calculated. Pacharin showed LC50 value of 78.9 plus or minus 1.8 mu g/mL. The structure of isolated compound was identified on the basis of their spectral data (IR, 1D- and 2D-NMR) and by comparison with literature spectral data. The results indicate pacharin as a potential natural larvicide.
Palavras-Chave: Molecular structure; Bioassays; Pesticides; Larvae; Metabolites; Toxicity tests; Mortality causes; Mortality; Data processing; Dichloromethane; Ethyl acetate; Methanol; Roots; Ethers; n-Hexane; Larvicides; Ethanol; Aedes aegypti; Bauhinia; Culicidae; Diptera
Imprenta: Parasitology Research, v. 112, n. 7, p. 2753-2757, 2013.
Descritores: Aedes aegypti - Molecular Structure ; Aedes aegypti - Larvicide
Data de publicação: 2013
