Isolation of diverse bioactive compounds from Euphorbia balsamifera: Cytotoxicity and antibacterial activity studies

摘要

Antibacterial and cytotoxic activities of Euphorbia balsamifera , fractions and pure compounds were evaluated.?The cytotoxic assays for?HCT116, HePG2 and MCF7 showed a significant IC 50 : 54.7 and 76.2?μg/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 n -butanol 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, 4- O -β-D-glucopyranosyl-2-hydroxy-6-methoxyacetophenone ( 4), 4- O -α-L-rhamnosyl-(1?→?6)-β-D-glucopyranosyl-2-hydroxy-6methoxy-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 -β-D-glucopyranosyl-2-hydroxy-6-methoxyacetophenone ( 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 IC 50 values to doxorubicin; 111.46, 42.67 and 44.90?μM against HCT116, HePG2 and MCF7, respectively, however, it is toxic on retina normal cell line RPE1.