Research Article
Benmerache A, Berrehal D, Kabo
Abstract
The secondary metabolites of butanol and ethyl acetate extracts of the endemic species Convolvulus fatmensis G. Kunze were separated by the use of different chromatographic techniques. The antioxidant activity of the butanol and ethyl acetate extracts was investigated and the antibacterial activity of the chloroform extract was tested against several Gram-positive and Gram-negative bacteria. Four known flavonols: quercetin (1), quercetin-3-O-b- glucoside (2), quercetin-3-O-b-galactoside (3), quercetin-3-O-rutinoside (4) were isolated from the ethyl acetate and butanol extracts. Compound 3 was new for the genus Convolvulus. A significant phenolic content (>33.74 g/100 g and >11.59 g/100 g of dry extracts) were found for the butanolic (BECF) and ethyl acetate (EACF) extracts, respectively. The EACF and BECF exhibited a good antioxidant activity (IC50 5.5 μg/ml, IC50 15 μg/ml) successively compared with the reference (rutin IC50 3.01 ± 0.2 μg/ml). The best antibacterial activity of the chloroformic extract of C. fatmensis (CECF) was observed against Proteus mirabilis, Staphylococcus aureus, Staphylococcus aureus ATCC 43300, Pseudomonas aeruginosa ATCC 27853, Pseudomonas aeruginosa, with 14, 13, 13, 11, 12 mm, inhibition zone diameters, respectively.