SILVA, Wellignton J.; DÓRIA, Grace Anne Azevedo.; MAIA, Rafael Trindade.; CARVALHO, Gílcia Aparecida de.; BLANK, Arie Fitzgerald.; ALVES, Péricles Barreto.; MARÇAL, Rosilene Moretti.; CAVALCANTI, Sócrates Cabral de Holanda.
Résumé:
The essential oils from leaves of Hyptis fruticosa (Lamiaceae) Salzm., H. pectinata (Lamiaceae) Poit., and Lippia gracilis (Verbenaceae)
HBK were investigated for their larvicidal activity against Aedes aegypti and analyzed by GC/MS. Fifty-nine compounds, representing
91.28–98.39% of the essential oils, have been identified. A standard solution was used to make 20 mL solutions ranging from 30
to 2000 ppm. Twenty larvae between third and fourth stages were added to the essential oil solution. A mortality count was conducted
24 h after treatment. Essential oils LC50 and their confidence limits at 95% probability were calculated by the methods of Reed-Muench
and Pizzi, respectively. The essential oil of Lippia gracilis showed potent insecticidal effect against Aedes aegypti larvae, the vector of
dengue fever. Carvacrol and caryophyllene oxide were the main responsible for the activity of L. gracilis and H. pectinata. Minor compounds
are probably acting synergistically to achieve H. fruticosa activity.
