Phytochemical investigation of Corchorus olitorius and Corchorus capsularis (Family Tiliaceae) that grow in Egypt

Background and objective Corchorus (Family Tiliaceae) is a genus of annual herbs. Nearly 40 species are known to occur in nature and distributed in the tropics of both hemispheres. Because of the wide medicinal applications of compounds isolated thereof, the present investigation deals with the isolation and structure elucidation of some phytochemicals from Corchorus olitorius (molokheya) and Corchorus capsularis that grow in Egypt. Materials and methods Phytochemical investigation of the seeds and different plant organs of both C. olitorius and C. capsularis was achieved applying different separation techniques. Petroleum ether extraction followed by saponification of the extract led to the isolation of phytosterols, hydrocarbons and fatty acids. Essential oils were obtained from the leaves by extraction with methylene chloride. Methanolic extraction led to the isolation of cardiac glycosides. Identification of isolated compounds was realized through Rf values, shift reagents and spectroscopic tools such as ultraviolet and nuclear magnetic resonance. The fatty acids were identified using gas liquid chromatography. Results and conclusion A study of the lipid contents (fatty acids, phytosterols and hydrocarbon components) of seeds, roots, leaves and stems of C. olitorius as well as the seeds and vegetative part of C. capsularis, which grow locally in Egypt, was carried out. The identification of the lipid content was achieved by comparing the retention time of their peaks in gas liquid chromatography with those of authentic samples. Gas chromatography/mass spectrometry study of the chemical constituents of the essential oils of the leaves of C. olitorius and C. capsularis led to the identification of 11 and 21 compounds with a total concentration of 24.7 and 62.9%, respectively. Cedrane-5-one (17.7%) and γ-terpinene (12.1%) represent the major compounds in each plant, respectively. Phytochemical investigation of C. olitorius led to the isolation of raffinose I, coroloside II, glucoevatromonoside III, erysimoside IV and olitoriside V and gluco-olitoriside VI. Meanwhile, the study of the vegetative parts of C. capsularis led to the isolation of 3-O-glucopyranosyl-β-sitosterol VII. The isolated compounds were identified by spectral tools (hydrogen-1, carbon-13-nuclear magnetic resonance, electron ionization mass spectrometer).