Essential Oil Analysis by GC-MS and Analgesic Activity of Lippia citriodora and Citrus limon

Abstract

The aim of the study was to characterize the chemical composition and biological properties of the essential oil from the plant Lippia citriodora and Citrus limon grown in Iraq. The essential oils were extracted by hydro-distillation method and analyzed by gas chromatography-mass spectrometry GC-MS. The essential oils of aerial parts of L. citriodora and C. limon peels were also examined for their analgesic effects by acetic acid writhing reflex and hot plate test method. The essential oil of aerial parts of L. citriodora yielded 27 compounds amounting to 87.92 % and essential oil of C. limon peels yielded 24 compounds amounting 97.28 %. The major constituents of EO of aerial parts of L. citriodora were citral (20.21 %), neral (14.37 %), myrcene (8.50%), geraniol (7.45 %) and caryophyllene (5.45 %) and linalool (1.59 %). The major constituents of essential oil of C. limon peels were limonene (29.52 %), β-pinene (23.89 %), citronellal (11.53 %) and thymol (9.79 %). The essential oils of aerial parts of L. citriodora and C. limon peels shows dose dependent analgesic effects in both acetic acid writhing reflex and hot plate test. Our study demonstrates that L. citriodora and C. limon has analgesic action due to presence of volatile constituents of respective plants.