Basil (Ocimum spp.), belonging to the Lamiaceae family, is a pleasent by smelling perennial shrub which grows in several regions all over the world (AKGÜL 1993; BARIAUX et al. 1992). Basil is one of the species used for the commercial seasoning. It is commonly known that the presence of essential oils and their composition determine the specific aroma of plants and the flavour of the condiments. Many species of aromatic plants belonging to the Lamiaceae family grow wild in the Mediterranean basin (AKGÜL 1989; MAROTTI et al. 1996; SANDA et al. 1998; MARTINS et al. 1999). There are usually considerable variations in the contents of the major components within this species. In a study of essential oils of different geographical origins, LAWRENCE (1988) found that the main constituents of the essential oil of basil are produced by two different biochemical pathways, the phenylpropanoids (methyl chavicol, eugenol, methyleugenol and methyl cinnamate) by the shikimic acid pathway, and the terpenes (linalool and geraniol) by the mevalonic acid pathway. Basil is a condimental plant cultivated in some parts of Turkey, and used frequently in soups, desserts, pickles, pizza, spagetti sauce, egg, cheese dishes, tomate juice, dressings, confectionery, salads, meat products etc. as a flavouring agent. Also, basil is well known as a plant of a folk medicinal value and as such is accepted officially in a number of countries (HEATH 1981; LAWRENCE 1985). The leaves of basil are also used in folk medicine as tonic and vermifuge. Also, basil tea taken hot is good for treating nausea, flatulance and dysentery (BAYTOP 1984). Basil is used in pharmacy for diuretic and stimulating properties, in perfumes and cosmetics for its smell; in fact, it is a part of many fragrance compositions (BARIAUX et al. 1992; KHATRI et al. 1995). Its oil has been found to be beneficial for the alleviation of mental fatigue, colds, spasms, rhinitis, and as a first aid treatment for wasp stings and snake bites. The essential oil has antifungal, physicochemical and insect-repelling activity (LAHARIYA & RAO 1979; DUBE et al. 1989; ÖZCAN 1998; MARTINS et al. 1999). It is also regarded as highly antiseptic and has been applied in boths to prevent postpartum infections. One can inhale the vapours of the infusion of the leaves of O. minimum or take a bath to improve the general conditions and to ameliorate the respiratory function (MARTINS et al. 1999). Source MUSA ÖZCAN1 and JEAN-CLAUSE CHALCHAT2 Essential Oil Composition of Ocimum basilicum L. and Ocimum minimum L. in Turkey Czech J. Food Sci. Vol. 20, No. 6: 223–228