Determinación de la actividad inhibitoria de acetilcolinesterasa y butirilcolinesterasa del extracto de alcaloides de Hippeastrum sp.

El objetivo fue determinar la actividad inhibitoria de acetilcolinesterasa y butirilcolinesterasa del extracto alcaloidal de Hippeastrum sp., especie vegetal que pertenece a la familia Amaryllidaceae. Los alcaloides se extrajeron mediante el proceso de maceración con solventes orgánicos y cambios de pH con un rendimiento de extracción de 0.95 %. Para identificar los alcaloides que se encuentran en el bulbo de Hippeastrum sp. se efectuó Cromatografía de Gases acoplada a Espectrometría de Masas. Para la determinación de la actividad inhibitoria de acetilcolinesterasa y butirilcolinesterasa se utilizó el método colorimétrico de Ellman et al. (1961), con modificaciones de Ortiz et al (2016), siendo galantamina el compuesto de referencia. Se evaluaron las actividades inhibitorias variando la concentración del cosolvente. Se realizaron tres repeticiones consecutivas para obtener la curva de inhibición enzimática con cuya ecuación de la recta se calculó la concentración inhibitoria máxima media (IC50). En la cromatografía de gases acoplada a espectrometría de masa (CG-EM) se identificaron 4 alcaloides, siendo el más representativo montanina con 22.7540 (ug gal/100 mg PS), seguido de tazetina con 14.8693 (ug gal/100 mg PS), y en menor cantidad crinina y licorina con 10.99440 y 10.2120 (ug gal/100 mg PS), respectivamente. El extracto alcaloidal de Hippeastrum sp., mostró una actividad inhibitoria alta frente a acetilcolinesterasa con un valor de IC50 de 7.25 ± 0.11 ug/ml, en relación al compuesto de referencia galantamina con IC50 DE 0.37 ± 0.03 ug/ml. La actividad inhibitoria frente a butirilcolinesterasa fue medianamente alta con un IC50 de 105.06 ± 2.14 ug/ml, respecto a galantamina que presento IC50 de 16.03 ± 0.77 ug/ml. Se observa que existe mayor afinidad por la enzima acetilcolinesterasa. Se recomienda realizar más estudios sobre la especie Hippeastrum sp.The objective was to determine the inhibitory activity of acetylcholinesterase and butyrylcholinesterase from the alkaloidal extract of Hippeastrum sp., a plant species that belongs to the Amaryllidaceae family. The alkaloids were extracted by the process of maceration with organic solvents and pH changes with an extraction yield of 0.95%. To identify the alkaloids present in the bulb of Hippeastrum sp. Gas Chromatography coupled to Mass Spectrometry was performed. For the determination of the inhibitory activity of acetylcholinesterase and butyrylcholinesterase, the colorimetric method of Ellman et al. (1961), modified by Ortiz et al. (2016) was used, the reference compound being galantamine. The inhibitory activities were evaluated by varying the concentration of the cosolvent. Three consecutive repetitions were performed to obtain the enzyme inhibition curve with which equation of the line, the mean maximum inhibitory concentration (IC50) was calculated. In the gas chromatography coupled to mass spectrometry (GC-MS) 4 alkaloids were identified, the most representative being montanin with 22.7540 (ug gal/100 mg PS), followed by tazetine with 14.8693 (ug gal/100 mg PS), and in smaller quantity crinina and licorina with 10.99440 and 10.2120 (ug gal/100mg PS), respectively. The alkaloidal extract of Hippeastrum sp., showed a high inhibitory activity against acetylcholinesterase with an IC50 value of 7.25 ± 0.11 ug/ml, in relation to the reference compound galantamine with IC50 of 0.37 ± 0.03 ug/ml. The inhibitory activity against butyrylcholinesterase was moderately high with an IC50 of 105.06 ± 2.14 ug/ml, compared to galantamine that presented IC50 of 16.03 ± 0.77 ug/ml. It is observed that there is greater affinity for the acetylcholinesterase enzyme. Further studies on the species Hippeastrum sp. is recommended