Evaluación de la actividad inhibitoria del extracto de alcaloides de Ismene narcissiflora sobre acetilcolinesterasa y butirilcolinesterasa.

Abstract

The main objective of this research work was to determine the inhibitory activity of the alkaloid extract of Ismene narcissiflora, on the enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The Amaryllidaceae family has been extensively studied because in its chemical composition presents alkaloids of isoquinolinic type, with great pharmacological activity, being galantamine the most relevant alkaloid due to its use in the treatment of Alzheimer’s disease. Firstly, the dry bulb of Ismene narcissiflora was macerated in methanol and subsequently used organic solvents (diethyl ether and ethyl acetate) with pH changes, obtaining an extraction yield of 0.248%. A total of four alkaloids were identified in the bulb of Ismene narcissiflora using Gas Chromatography coupled to Mass Spectrometry (CG-EM) being: tazetine (78.29%), lycoramine (18.96%), galantamine (10.15%) and O-methyleukotamine (9. 8507%). To evaluate the inhibitory activity of acetylcholinesterase (AChE) and butyrilcolinesterase (BuChE), the method of Ellman et al. (1961) was used, with modifications made by Ortiz (2016), using galantamine as reference compound. As a result of the enzymatic inhibition, for AChE an IC50 value of 23,543 ± 0.316 ug / mL was obtained and for the reference compound galantamine presented an IC50 of 0.585 ± 0.006 ug / mL. As regards the inhibition shown in BuChE, an IC50 value of 255,953 ± 3,423 ug / mL was obtained while in galantamine it presented an IC50 of 12,302 ± 1,974ug / mL. The results obtained showed a high inhibitory activity on AChE and a null activity on BuChE, after comparing them with the reference compound galantamine. It is recommended to carry out more phytochemical and pharmacological studies on the genus Ismene since many of its species could have alkaloids of great interest.