Abstract :

Pistacia palaestina Boiss (P. palaestina) is a medicinal plant with multiple dietary and therapeutic applications. The purpose of this work was to investigate the phytochemical content, the antioxidant, and the anti-acetylcholinesterase (AChE) activities of the P. palaestina leaves’ methanol extract. The antioxidant activity of the extract was tested by 2,2 -azino-bis-3 ethylbenzothiazoline-6-sulfonic acid (ABTS.+) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays, while the AChE inhibitory activity of the extract was determined according to Ellman’s assay. The composition of secondary phytochemical metabolites was established by HPLC-PDA and GC-MS analysis. P. palaestina leaves displayed strong ABTS•+ as well as DPPH radical scavenging ability with an IC50 value (6.86 µg/mL and 8.31 µg/mL) close to that of ascorbic acid (6.09 µg/mL and 6.96 µg/mL), respectively. For enzyme inhibition, the P. palaestina extract showed good activity against acetylcholinesterase in a dose-dependent manner with IC50 (57.67 μg/mL) ten folds higher than the standard inhibitor galantamine (IC50 = 5.64 μg/mL). The methanol extract displayed high phenolic (242.2 mgGAE/g extract) content. Similarly, the phytochemical profiling of the extract cautiously identified 19 different secondary metabolites, as accessed by HPLC and GC-MS analyses. Benzofenac methyl ester, 3,5-bis(1,1- dimethylethyl)- phenol, N-Dimethylaminomethyl-tertbutyl-isopropylphosphine, 14-methylPentadecanoic acid methyl ester, 13-Tetradece-11-yn-1-ol, and Tridecane were the main compounds detected. Based on the current findings on the antioxidant and anti-AChE activities of P. palaestina methanol leaves extract, this plant may be recommended as a source of bioactive plant compounds and presents new alternatives for use in the management of neurological diseases