Phytochemical standardization of Eucalyptus tereticornis Smith (Myrtaceae) used in Green Pharmacy from Northeastern Brazil

Abstract

IntroductionEucalyptus tereticornis Smith. is used in the Green Pharmacies Project in the state of Ceará, Brazil, for the treatment of respiratory ailments. Its major essential oil content is 1,8-cineole. Until the present time, there is no phytochemical standardization. Therefore, the present study was aimed at standardization by phytochemical studies and comparison of the leaves of E. tereticornis Smith. (Myrtaceae) used in the Green Pharmacies (Programa Farmácia Viva) of the Northeast Brazilian region, Ceará at different seasons. Material and methodsThe leaves were collected from the matrix plant and its clones located in Fortaleza, Ceará. Preliminary phytochemical analysis, extraction and analysis of essential oils using Gas Chromatography coupled to Mass Spectrometry (GCMS) were carried out. The mass spectra obtained was compared with that from the late Professor Francisco José de Abreu Matos' scientific collection. The fluid extract was prepared and analysed using HPLC. ResultsPhytochemical studies on the fresh leaves of E. tereticornis demonstrated the presence of coumarins, flavonoids, saponins and tannins in all the accessions. The essential oils presented 1,8-cineole as the major compound, in addition α-pinene, β-pinene, p-cymene, limonene, γ-terpinene, α-terpineol and aromadendrene were identified. The fluid extract presented 1,8-cineole (7.68 %) and coumarin (6.2 ×10−3%), both can serve as important chemical markers. ConclusionThe percentage of 1,8-cineole of essential oil in the accessions of E. tereticnornis studied is in accordance with the Brazilian pharmacopeia. The phytochemical profile of the matrix plant has remained relatively stable since 1994. Coumarin presence is reported for the first time in this species.