Avaliação da toxicidade e atividade moluscicida do óleo essencial Cinnamomum zeylanicum Blume contra o caramujo Biomphalaria glabrata (Say, 1818)

Abstract

This work determines the toxicity and the molluscicidal effect of the oil extracted from the leaves of Cinnamomum zeylanicum Blume against the snail Biomphalaria glabrata (Say, 1818). For this, the essential oil was extracted quantitatively by hydrodistillation. Then, quantifications of its components were performed by gas chromatography coupled to mass spectrometry (CG-MS) and the toxicity and molluscicidal activity of the oil were tested, respectively, against Artemia salina and snails Biomphalaria glabrata (Say, 1818). The lethal concentration (LC50) was calculated from the Reed-Muench & Pizzi methods, respectively, for toxicity and molluscicide testing. The results of the chromatographic analysis showed that the oil has 83% eugenol (majority constituent) and 2.5% humulene (minority component). In the toxicity evaluation, the oil was considered to be moderately toxic with a LC50 of 162.1 mg.L-1 ± 2.80, with a 95% confidence interval, while the molluscicidal activity presented a lethal concentration of 50% (LC50) of 18.62 mg. L-1 ± 2.18, with a 95% confidence interval. Therefore, the oil is active against the snail Biomphalaria glabrata.