Chemical study of the constituents of Eriosema glomeratum and cytotoxicity of some isolated compounds.

INTRODUCTION: Cancers have the ability to develop resistance to traditional therapies, and the increasing prevalence of these drug resistant cancers necessitates further research and treatment development. This work was designed to the isolation of compounds from the roots of E. glomeratum (Guill. & Perr.) Hook.f. and evaluation of their cytotoxicity. This plant is a member of the Fabaceae family used in folk medicine for the treatment of wounds, venereal diseases, helminths and skin diseases.
METHODOLOGY: Repeated silica gel column chromatography followed by Sephadex LH-20 were used to isolate ten compounds and the structures of these compounds were identified by spectroscopic analyses (NMR and MS), and comparison with published data. The evaluation of the cytotoxicity of some among these compounds was carried out by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay (MTT; Nacalai Tesque, Japan), according to the published procedure (Mosmann, 1983).
RESULTS: The phytochemical study led to the isolation of two new compounds and thirteen known compounds including eriocaffeate (1), erioceramide (2), genistein (3), genistin (4), lupinisoflavone A (5), quercetin (6), erioschalcone A (7), erioschalcone B (8), two alcohols (9 and 10), lupeol (11), a mixture of β-sitosterol (12a) and stigmasterol (12b), and β-sitosterol-3-O-β-D-glucopyranoside (13). The cytotoxicity of compounds from 1 to 6 was evaluated against three human cancer cell lines. Compounds 3 and 6 possessed activities on all the tested three cell lines, MCF7 (IC50 = 88.9 and 42.6 μM), A549 (IC50 = 42.1 and 28.2 μM) and HeLa (IC50 = 27.4 and 19.1 μM), respectively. Compound 4 was specifically active with moderate activity (IC50 = 68.7 μM) on the human cervical HeLa cancer cell line, while the new compounds 1 and 2 did not show any activity against all cell lines at the tested concentrations.
CONCLUSION: Our findings from the isolation and characterization of the new caffeic acid ester (1) and the new ceramide (2), along with eleven known compounds (3-13) from the roots of E. glomeratum as well as the cytotoxicity of some of these isolated compounds on human cancer cell lines are relevant for the search of bioactive secondary metabolites from species of the genus Eriosema.
IMPACT OF THE STUDY: By this approach, we can fight anticancer resistance.
Keywords: Eriosema glomeratum, Fabaceae, Roots, anticancer, Cytotoxicity.