ALKALOIDS ISOLATED FROM HIPPEASTRUM RETICULATUM (L’HÉR.) HERB. AND THEIR ACETYLCHOLINESTERASE INHIBITORY ACTIVITIES

Abstract

Background: Hippeastrum reticulatum (L.Hér.) Herb is a species of the Hippeastrum Herb. genus. Screening studies have shown that this species has the ability to inhibit the enzyme acetylcholinesterase. So far, research on this species is still very limited. The purpose of this study is to provide some more informations about the chemical composition and bioactive of isolated compounds from this species. Materials and method: Bulbs of Hippeastrum reticulatum was collected in Thua Thien Hue province in May 2018. The compounds were isolated by using various chromatographic methods and their structures were identified by 1D and 2D-NMR spectroscopic methods in reference to the literature. The acetylcholinesterase inhibitory activity was determined by Ellman’s microplate colorimetric method. Results and conclusions: Two alkaloids including N-methyltiramine (1), narciclasine-4-O-β-D-xylopyranoside (2) was isolated from bulbs of Hippeastrum reticulatum (L’Hér.) Herb. These compounds were isolated from Hippeastrum Herb. genus for the first time. Compound 2 showed moderate acetylcholinesterase inhibitory activity, with IC50 value of 70.06 ± 1.46 µg/mL. Key words: Hippeastrum reticulatum (L’Hér.) Herb., alkaloid, N-methyltiramine, narciclasine-4-O-β-Dxylopyranoside.