A COMPREHENSIVE REVIEW ON LEMONGRASS (CYMBOPOGON CITRATUS) OIL EXTRACTION AND ITS APPLICATIONS

This article presents a comprehensive review of methods of extraction, properties, compositions and industrial application of lemongrass essential oil. Lemongrass (Cymbopogon citratus) essential oil has been used traditionally since ancient days in medicine as remedy to improve blood circulation, treat fever and malaria, promote digestion and as well used to increase immune system of the human body. Essential Oils of lemongrass are used in various industries. Some of the industries in which they are used extensively include Aromatherapy, Food and drink industry, Pharmaceuticals industry, Fragrance and Flavour industry, Agriculture and Livestock industry, Cosmetic and Soaps industry, House hold and Domestic. The quality of the essential oil from lemongrass strongly depends on the extraction method and operating conditions. Basically lemongrass essential oil can be obtained by various extraction methods, such as steam distillation, conventional solvent extraction, Soxhlet extraction, ultrasound-assisted extraction (UAE), hydrodistillation (HD), microwave-assisted hydrodistillation (MAHD), Simultaneous-distillation-extraction technique (SDE), Solvent-Free-Microwave-Extraction Technique (SFME) and supercritical fluid extraction (SFE) with CO2. The composition of essential oil of Cympobogon citratus contains α-pinene, β-pinene, delta-3-catrene, myrcene dipentene, β-phellandrene, β-cymene , methyl heptanene, citronellal, β-elemene, β-caryophyllene, citronellyl acetate, geranyl acetate , citral A , citral B, geraniol, elemol , and β-caryophyllene oxide, etc. In addition, lemongrass oil also contains essential minerals such as Fe, Zn, Mg, Na, K, Ca, Mn, P etc. The most important physicochemical properties of lemongrass oil includes specific gravity, Optical rotation, refractive index, percentage of citral, freezing point, moisture content, acid value, ester value, carbonyl value and phenol content . Nevertheless, the chemical composition of the essential oil of Lemongrass also varies with the geographical origin, cultivation practices, plant age, photoperiod, harvest period, cultivars, and extraction methods. However, for extraction of lemongrass oil, green technology such SFE, SDE, SFME and MAHD that are consumer and environmental friendly in industrial-scale essential oil production should be considered as a method to overcome the limitations of traditional distillation methods. KEYWORDS: Essential Oil, Lemongrass, Microwave-Assisted-Hydrodistillation. Solvent Extraction, Steam Distillation, Supercritical Fluid Extraction