Ammoniacum gum is traditionally used as an expectorant, stimulant, antispasmodic, catarrh, asthma, chronic bronchitis, and enlargement of liver and spleen in Medicine. The Soxhlet extraction of the oleo gum resin of D. ammoniacum was carried out with organic solvents including hexane, dichloromethane, chloroform, ethyl acetate, and methanol. The screening of the anti-alzheimer activity of the extracts was measured by acetylcholinesterase (AChE) inhibitory activity, and the hexane (IC50 = 32.34 μg/ml) and chloroform (IC50 = 43.5 μg/ml) extract performed highest activity. A profiling experiment of the chloroform extract conducted by LC-MS and literature resources suggested six potential biologically active compounds including doremone A (1), kopetdaghin E (2), dshamirone (3), kopetdaghin D (4), kopetdaghin C (5), and ammodoremine (6). To confirm the responsibility of these compounds for the observed AChE inhibitory activity, the molecular docking studies of these compounds were performed with AChE enzyme which indicated that these compounds show higher AChE inhibitory activity than galantamine as positive control. The molecular docking study was carried out using Glide.
