Elucidación estructural y actividad antioxidante de metabolitos del extracto de hojas de Tristerix chodatianus

Introduction: The species Tristerix chodatianus (Pastochovsky) “pupa” possesses antioxidant and antimicrobial activity and its ethyl acetate extract is the most active, containing phenolic compounds such as flavonoids and tannins. Objective: To determine the structure and antioxidant activity of secondary metabolites obtained from the ethyl acetate extract of Tristerix chodatianus (Pastochovsky) “pupa” leaves. Methods: The extract was obtained by the reflux method, using solvents of increasing polarity and isolation of secondary metabolites by rapid fractionation under vacuum and successive chromatographic columns, using Sephadex LH-20 and silica gel G-60. The fractions obtained were pooled by thin layer chromatography and the final products purified by preparative thin layer chromatography. Structural elucidation of the secondary metabolites was based on data obtained by ultraviolet proton nuclear magnetic resonance (1H NMR) and carbon 13 nuclear magnetic resonance (13 C NMR) spectroscopic techniques. Results: Flavonoids, rutin, quercetin and quercitrin were obtained as major products. Antioxidant activity by the 2,2-diphenyl-1-picrylhydrazyl radical method indicated that the flavonoid quercetin was the most active of the metabolites present. Conclusion: The compounds mostly responsible for the antioxidant activity of Tristerix chodatianus leaf extract are flavonoid in nature.