Phenolic composition and prospective anti-infectious properties of Atriplex lindleyi

ObjectiveTo investigate the antiplasmodial, antimicrobial, radical scavenging effects and to identifiy the phenolic constituents of Atriplex lindleyi (A. lindleyi).MethodsA. lindleyi extracts and some isolated compounds were tested in vitro against the chloroquine-resistant strains of Plasmodium falciparum. The radical scavenging activity was quantified by using 2,2-diphenyl-2-picrylhydrazyl nitrogen-centered free radical. The IC50 of each extract was compared with references. The in vitro anti-infectious activity of extracts was evaluated against representative Gram-positive and Gram-negative bacterial strains [Staphylococcus aureus CIP 4.83, Enterococcus hirae CIP 5855, Pseudomonas aeruginosa (P. aeruginosa) CIP 82118, Escherichia coli CIP 53126], and fungal species [(Candida albicans (C. albicans) IP 48.72, Aspergillus niger IP 1431.83]. Ethanol extract was investigated for chemical composition through column and high performance liquid chromatography. The isolated compounds were identified by mass spectrometry and nuclear magnetic resonance.ResultsQuercetin-7-O-arabinopyranoside-3-O-neohesperidosides (1), quercetin-3-O-arabinopyranosyl(1→6) glucopyranoside (2), quercetin-3-O-glucopyranoside-7-O-rhamnopyranoside (3), quercetin-3-O-glucopyranoside-7-O-arabinoside (4), schaftoside (5), quercetin-7-O-glucopyranoside (6) were isolated for the first time from the ethanol extract of A. lindleyi aerial parts in addition to isorhamnetin-3-O-β-glucopyranoside (7) and quercetin (8). The extracts exhibited moderate antiplasmodial activity with IC50≈ranging from 10–50 μg/mL. Quercetin was the most potent compound with IC50 of 9 µg/mL. P. aeruginosa and C. albicans were the most susceptible organisms.ConclusionsThe study implies that A. lindelyi can contribute to the fight against malaria, and be useful as prophylactic against C. albicans and P. aeruginosa.