Abstract
Antibacterial and cytotoxic activities of Euphorbia balsamifera, fractions and pure compounds were evaluated. The cytotoxic assays for HCT116, HePG2 and MCF7 showed a significant IC50: 54.7 and 76.2 mu g/mL of non-polar fraction "n-hexane" against HCT116 and HePG2, respectively. Antibacterial results revealed that plant fractions exhibited significant potential against the tested pathogens than the total extract where n-butanol and ethyl acetate fractions showed significant antibacterial activity (P < 0.05) against tested bacterial strains. Isolation and structure determination of compounds from n-hexane and nbutanol fractions were performed. From n-hexane fraction, 29-nor-cycloartanol (1), lanost-8-en-3-ol (2a), cycloartanol (2b) and kampferol-3,4'-dimethyl ether (3) were isolated and structurally identified, along with 24 compounds were tentatively identified by GC-MS. From the polar n-butanol fraction, 4O-beta-D-glucopyranosyl-2-hydroxy-6-methoxyacetophenone (4), 4-O-alpha-L-rhamnosyl-(1 -> 6)-beta-D-gluco pyranosyl-2-hydroxy-6-methoxy-acetophenone (5), quercetin-3-O-glucopyranoside (6) and isoorientin (7) were assigned. Structures of the obtained compounds were determined by nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry. Except compounds 1 and 5, all reported compounds announced antibacterial efficiency. Compound 2 showed selectively the highest activity against Enterococcus faecalis (22 +/- 0.13 mm), meanwhile 4-O-beta-D-glucopyranosyl-2-hydroxy-6-methoxyaceto phenone (4) showed broadly the highest antibacterial activity with MIC of 1.15-1.88 mg/mL against the test Gram-positive and Gram-negative bacteria. Cytotoxic assays indicated that kampferol-3,4'-dimethyl ether (3) exhibited the highest activity with matching IC50 values to doxorubicin; 111.46, 42.67 and 44.90 mu M against HCT116, HePG2 and MCF7, respectively, however, it is toxic on retina normal cell line RPE1. (C) 2020 The Author(s). Published by Elsevier B.V. on behalf of King Saud University.