Determinación del potencial inhibitorio de la fracción alcaloidal de Psychotria stenostachya sobre xantina oxidasa y radical superóxido mediante autografía.

Abstract

The main objective of this investigation was to determine the inhibitory potential of the alkaloidal fraction of Psychotria stenostachya on xanthine oxidase and superoxide radical by autography. In the first instance, an alcoholic maceration process of the leaves of P. stenostachya with methanol was carried out, for the subsequent liquid extraction of total alkaloids with organic solvents by means of pH variations, reaching a yield of 0.76%. Next, the components of the alkaloidal extract were separated through TLC, using chloroform / triethylamine / methanol as mobile phase in proportions (6: 0.5: 0.6) and developed in a UV chamber at 254 nm. Autograph tests were performed on TLC plates by means of the "dot blot" technique; 10 µ L of each solution was seeded at concentrations of 100, 50, 10, 5 and 1 µg using methanol as solvent. For the evaluation of the antioxidant potential of P.stenostachya, ascorbic acid was used as a standard for the DPPH * model, while for the determination of superoxide radical uptake taxifoline was used as a standard for the models: RIBOFLAVINA / LUZ / NBT and NADH / PMS / NBT. Finally, allopurinol was used as standard and xanthine as a substrate for the evaluation of inhibitory capacity on XO. In this way, a distinction is made between pure XO inhibitor and a 𝑂2∙ − scavenger. The results were presented qualitatively through changes in color and halo diameter. With respect to quantitative data, these were recorded using the GelAnalyzer program to determine the area of inhibition. As a result, the alkaloidal fraction of P. stenostachya was obtained having significant antioxidant capacity by being able to capture superoxide radical; however, it lacks inhibitory activity on Xanthine Oxidase since it did not show a reaction. It is recommended; more studies and analysis regarding the chemical and structural composition of the plant species.