Characterization and physico-chemical analysis of essential oil of Cymbopogon citratus leaves

Abstract

The genus Cymbopogon is important from the point of view of their essential oils. Essential oils from these species are widely used in flavours, fragrances, cosmetics, soaps, detergents and perfumery owing to their typical lemon-like aroma. Essential oil of Cymbopogon citratus was extracted by hydrodistillation and characterized using Gas chromatography/mass spectrometry (GC-MS) and Fourier Transform Infrared (FTIR).The oil was also subjected to physico-chemical analysis, the physical and chemical properties evaluated were Boiling point (74^oC), Specific gravity (0.8960), Refractive index (1.4838) and pH (6.00) at 25^oC. Saponification value(109.76) and Acid value (0.55) mg KOH/g oil. Iodine value (100g of I₂/g oil) 105, Ester value (189.21), Residue on evaporation (10%) at 100^oC.The chemical composition of the essential oil analyzed by GC-MS showed citral (31.1%), β-Myrcene (14.2%), citronellal  (9.8%), limonene  oxide (7.7%), eraniol (7.3%) and linalool (6.2%) as the major compounds. The FTIR spectra revealed the presence of n-alkane, conjugated alkene, primary amide, amine, aldehyde, primary and secondary alcohols. The results obtained from the physico-chemical parameters, and functional groups identified by FTIR as well as the compounds identified by GC-MS revealed that the oil has medicinal and nutritive values as well as industrial applications in the pharmaceutical, perfumery and cosmetic industries .

Keywords: Characterization, Citral, Cymbopogon citratus, Essential oil, FTIR, GC-MS