Chemical Composition and Larvicidal Activity of Essential Oil from the Rhizomes of Amomum rubidum Growing in Vietnam

This work reports the chemical constituents and larvicidal activity of essential oil from Amomum rubidum Lamxay & N. S. Ly. The essential oil was extracted from the air-dried rhizome in an all-glass Clevenger-type apparatus and characterized by gas chromatography (GC-FID) and gas chromatography/mass spectrometry (GC/MS) on HP-5 column. The larvicidal property was evaluated against the fourth-instar larvae of Aedes aegypti according to the protocols of the World Health Organization. A. rubidum essential oil was characterized by high amounts of beta-phellandrene (16.1 %), limonene (14.4 %), and delta-3-carene (13.9 %). The oil displayed larvicidal activity against Ae. aegypti with minimum lethal concentration, LC50 values of 22.85 and 22.62 mu g/mL respectively at 24 h and 48 h, while the LC50 values of 31.44 mu g/mL and 31.03 mu g/mL were obtained respectively at 24 h and 48 h. The chemical constituents and larvicidal actions of A. rubidum rhizome essential oils are being reported for the first time.