A Potential Role of Alkaloid Extracts from Salsola Species (Chenopodiaceae) in the Treatment of Alzheimer's Disease

From the aerial parts of Salsola oppositofolia, S. soda and S. tragus an alkaloid extract was obtained and tested to evaluate antioxidant and anti-cholinesterase activities. The in vitro study of the antioxidant activity by the DPPH method revealed a significant activity of Salsola alkaloid extracts with IC(50) values ranging from 16.30 microg/mL for S. oppositifolia to 26.17 microg/mL for S. tragus. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities were evaluated. S. tragus alkaloid extract exerted the highest inhibitory activity against AChE (IC(50) of 30.2 microg/mL) and BChE (IC(50) of 26.5 microg/mL). Interestingly, S. soda and S. oppositifolia exhibited a selective inhibitory activity against BChE with IC(50) values of 34.3 microg/mL and 32.7 microg/mL, respectively. Tetrahydroisoquinoline alkaloids were identified and quantified by GC/MS analysis.