1.1 Background of the Study
Lemongrass (Cymbopogon citratus) is an aromatic plant which grows in many part of tropical and sub-tropical south-east Asia and Africa, Cymbopogon citratus is a member of sub-family poaceae of the grammae and it belongs to the ropogonae. Most of the species of lemon grass are nature to South Asia, South-east and Australia. Cymbopogon citratus is called the West India lemon grass because it has its origin in the Malaysian region. Related species is Cymbopogon flexuosus called the East Indian lemon grass or Cochingrass; it has the origin in Ludo-Burma region and is native to Indian and Thailand. Both the species are today cultivated throughout tropical Asia. Cymbopogon citratus is usually found in the north region in Nigeria, it can also be found in the Kaduna south and partly Easter and Western Nigeria (Oloyede, 2009).
Lemongrass essential oil is characterized by a high content of citral which is used as a raw material for the production of vitamin A and beta carotene.The chemical composition of lemon grass essential oil vary widely as a function of genetic diversity, habitat and agronomic treatment of the culture (Matasyoh et al., 2011).
In food, cosmetics and pharmaceutical industries, the extraction of essential oil from natural sources with supercritical fluids is a promising alternative to conventional processes, such as solvent extraction (Reverchon, 2006).
This interest is due to the possibility of obtaining solvent free extracts and the low temperature employed which is an attractive way to preserve the quality of thermo- sensitive products carbondioxide is an appropriate solvent entail oil extraction from natural products, since it is readily available, non-toxic and non-inflammable and has a low reactivity (Reverchon, 2006).
It is well known that SF properties can be turned by manipulation of temperature and pressure enabling the obtainment of essential oils, with different chemical compositions. Some works can be found in the literature regarding the use of supernatural fluids for fractionation of citrates essential oil. An alternative is to employ molecular sieves as adsorbents to concentrates the oil in some compounds or classes of compounds (Reverchon, 2006).
Cymbopogon citratus belong to the grammae family and therefore related to the grain crops, it requires a warm climate with plenty of sunshine. In India, it is known as “Choomana poolu” and is also referred to as “Indian Verbena” or Indian Melissa oil” and used in Ayurvedic medicine to help bring down fevers and treat infectious illnesses. It is a valuable ingredient in perfumes and citru-type soaps and is also an insect deterrent (Mohammed et al., 2012).
To the French, it is Citronelle, Portuguese Citronelle but in Nigeria, the Edo’s call it Eti, Efik Ikoneti, Hausa Tsaur, Ibibio Myoyaka makara, Igbo (Owerri) Acharaehi and Yoruba Kooko Oba (Mohammed et al., 2012).
1.2 Statement of Problem
Different plants or plant parts are known to yield essential oils. It is considered important to establish the quantity of the yields in some parts of lemongrass and also characterize the oil to show the physiochemical properties of the oil.
1.3 Objective of the Study
1.4 Scope of the Study
The scope of this study is designed to cover the extraction and characterization of essential oil from lemongrass.
1.5 Significance of the Study
This study will be of immense benefit to everybody in all walks of life, as many are ignorant or have little knowledge of what essential oil from lemongrass is and its benefits. In addition, to its intrinsic benefits to plants and being beautifully granted to people, essential oil from lemongrass have been used throughout history in many cultures for modern scientific study and trends towards more holistic approaches to wellness are driving a revival and new discovery of essential oil health application (Wong et al., 2005).
1.6 Research Questions