Chemical composition and larvicidal activity against Aedes aegypti L. (Diptera: Culicidae) of essential oils from leaves, stalks and roots of the Croton nepetaefolius Baill (Euphorbiaceae)

摘要

Croton nepetaefolius Baill is the aromatic plant native to northeast of Brazil popularly known as "marmeleiro sabiá". It is used in folk medicine as a stomachic, a carminative and for the treatment of intestinal colic. A total of 26 compounds were obtained by hydrodistillation and identified by GC-MS and CG-FID in the three essential oils samples, being 5 monoterpenes (36.9%), 7 sesquiterpenes (31.8%) and 1 Arylpropanoid (25.7%) in the essential oil of leaves, 6 monoterpenes (16.6%), 8 sesquiterpenes (14.1%) and 2 arylpropanoids (68.6%) in the essential oil of stalks and 7 monoterpenes (5.98%), 4 sesquiterpenes (4.52%) and 2 arylpropanoids (84.9%) in the essential oil of roots. The main constituents in the essential oil of leaves, stalks and roots are the monoterpene 1, 8-cineole (26.16%) and the arylpropanoids elemicin (60%) and methyl eugenol (46.31%), respectively. Essential oil of the leaves have been demonstrated larvicidal activity (LC 50 77.6 mg/mL), while the essential oils of the stalks (LC 50 134.9 mg/mL) and roots (LC 50 110 mg/mL) were considered not active. These results can be explained by the presence in the leaves essential oil from C. nepetaefolius of the monoterpenes sabinene, 1,8- cineole and terpinen-4-ol and sesquiterpenes β-caryophyllene and germacrene D natural products which have been reported to be active against A. aegypti.