Acetylcholinesterase Inhibitor From Tabernaemontana pandacaqui Flowers

Abstract

The inhibition of acetylcholinesterase (AChE) is still considered a strategy for the treatment of Alzheimer’s disease. The aim of this study was the search for potential drugs from natural sources which can inhibit AChE. The methanol extract of fresh flowers of Tabernaemontana pandacaqui was partitioned with n-hexane and ethyl acetate. All extracts were evaluated for AChE inhibitory activity. The ethyl acetate fraction, which showed the strongest AChE inhibitory activity, was fractionated using various chromatographic techniques, leading to the isolation of 6 compounds (1-6), which were identified mainly by spectroscopic techniques; this is the first report of these compounds from T. pandacaqui flowers. Astragalin (6) was the major active constituent. The structure-AChE inhibitory activity relationship of 6 and its derivatives was studied. The results suggest that T. pandacaqui flowers and its flavonoid compounds could be potentially used for the treatment of Alzheimer’s disease.