To investigate the phenolic profile and biological activities of Argania spinosa L. leaves.
The crude methanol extract of leaves of A. spinosa L. Skeels was obtained by ultrasonic
extraction, and the total polyphenolic and flavonoid contents were determined by ultra-high performance
liquid chromatography-electrospray ionization-quadrupole time-of-flight-mass spectrometry (UPLC-ESIQTOF-MS). In vitro antioxidant activity was determined by 2,2-di-phenyl-1-picryl-hydrazil (DPPH) radical
assay and antimicrobial activity evaluated using agar disk diffusion method against reference
pathogenic strains ( Bacillus subtilis
ATCC 6633, Bacillus cereus
ATCC 14579, Yersinia enterocolitica
ATCC 23715, Staphylococcus aureus
ATCC 25923, Pseudomonas aeruginosa
ATCC 25922). Cytotoxic activity was evaluated by methyl-thiazolyldiphenyl-tetrazolium
bromide (MTT) assay.
The results revealed abundant polyphenols and flavonoids (221.39 ± 5.70 μg GAEq/1 g and
66.86 ± 3.36 μg CAEq/1 g, respectively) in the leaf extract. UPLC-DAD-ESI-QTOF-MS profiling showed
the presence of myrecitin-3-galactoside, myrecitin-3-gluctoside, myrecitin-3-xyloside, quercetin-3-galactoside, quercetin-3-glucoside, quercetin-3-arabinofuranoside, and quercetin-3-rhamnoside. DPPH
assay of the leaf extract yielded a half-maximal effective concentration (EC50
) value of 125.60 ± 1.87 μg.
A. spinosa L. leaves exhibited antibacterial activity against Gram (+) and Gram (-) bacteria, with
particularly marked activity against B. subtilis
(inhibition zone, 16 mm). Cytotoxicity data showed that the
extract inhibited the proliferation of PC3 cells (IC50
~ 600 μg).
A. spinosa L. leaf extract is rich in valuable biologically active compounds and could
represent a new resource for natural and preventive therapies.