CHARACTERIZATION AND EVALUATION OF REPELLENT EFFECT OF
ESSENTIAL OIL OF MANGIFERA INDICA L. ON ANOPHELES GAMBIAE, FROM KENYA
Alwala.J.O, W. Wanzala
Department of Chemistry, Maseno University, P.O. Box 333- 40105,Maseno, Kenya
Abstract:
Ethnopharmacologically, the mango has a lot of applications in life in human health and ethnoveterinary medicines since ancient times. The study aimed at characterizing the essential oil of Mangifera indica L. leaves and evaluating its repellent effect on the host-seeking female Anopheles gambiae, the vector of African malaria. The essential oil was obtained by hydrodistillation and analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The repellent effect of the essential oil was evaluated using the human-bait technique to simulate field situation. Of the 26 major hydrocarbon compounds identified, α-pinene occurred in the largest amount (33.3 %), followed by α-phellandrene (22.6 %), Limonene (13.2 %), p-cymene (6.1 %), Heptane (3.8 %), β-pinene (2.6 %), Ledene (1.3 %), (-)-α gurjunene (1.2 %), β-myrcene (1.1 %), γ-terpinene (1.0 %), (+)-2-carene (0.9 %) and trans (β)-caryophyllene (0.9 %) in that order. The oil showed a significant dose-dependent repellent effect on host-seeking female Anopheles gambiae s.s. The oil showed a complex composition of hydrocarbon compounds and may be richer in monoterpenes than in any other type of compounds. It showed the potential to repel mosquitoes.