Composition of the essential oils of Ocimum canum, O-gratissimum and O-minimum

The essential oils of Ocimum canum, O. gratissimum and O. minimum grown in S. Tome, where they are used in Traditional Medicine mainly as febrifuge an d for the treatment of respiratory diseases, were investigated. The essenti al oils were obtained from the aerial parts by hydrodistillation and subseq uently analysed by GC, CC-MS and C-13-NMR. C-13-NMR spectroscopy proved to be an important tool, which can be very useful in the identification of mos t of the constituents. Major compounds in the volatile oil of O. gratissimu m were thymol (48.1%) and p-cymene (12.5%). The essential oil of O. canum w as characterized by its high content of trans-methyl cinnamate (79.7%), whe reas the most important oil constituent of O. minimum was linalool (52.7%).