ABSTRACT
Objectives: Ilex paraguariensis (Aquifoleaceae) is cultivated to produce "yerba mate". Due to its nutritional, energizing, hypoglycemic and antioxidant effects, it is used in the elaboration of food, pharmaceuticals, and cosmetics. The oxidative stress related to protein glycation and production of advanced glycation end products (AGEs) leads to the development of several diseases. The objective of this work was to compare the antioxidant and anti-AGEs activity of a decoction of fruits (F) and leaves (L). Methods: The antioxidant activity was assayed by the DPPH assay and the inhibition of egg yolk lipid peroxidation (ILP), and anti-AGEs activity, through the inhibition of the formation of fructosamine (IF), ß-amyloid (Iß), protein carbonylation (IC) and AGEs (IA). Polyphenols were quantified by HPLC. Results: Maximum response ± SEM For F 0.01 µg/mL IF = 42 ± 4%, IC = 17 ± 2% and for 10 µg/mL IA = 38 ± 4%, Iß = 67 ± 7%. For L 0.1 µg/mL IF = 35 ± 2%, IC = 19 ± 2% and for 100 µg/mL IA = 26 ± 3%, Iß = 63.04 ± 2%. The DPPH IC50 = 134.8 ± 14 µg/mL for F and 34.67 ± 3 µg/mL for L. The ILP IC50 = 512.86 ± 50 µg/mL for F and 154.8 ± 15 µg/mL for L. By HPLC L presented the highest amounts of flavonoids and caffeoylquinic acids. F and L showed strong anti-AGEs activity, affecting the early stages of glycation at low concentrations and the late stages of glycation at high concentrations. The highest activity for both F and L was seen in the IF and Iß. F presented the highest anti-AGEs potency. L presented the highest antioxidant potency, which was related to the highest content of polyphenols. Conclusion: The fruits of I. paraguariensis could be a source of antioxidant and anti-AGEs compounds to be used with medicinal purposes or as functional food.
ABSTRACT
Larrea divaricata Cav. is widely distributed in Argentina. Aqueous extract, of its leaves, has documented antitumoral and immunomodulatory activities. In this study, the antioxidant activity of aqueous extract and a component, nordihydroguaiaretic acid was determined and compared using different assays. Both the aqueous extract and nordihydroguaiaretic acid exhibited antioxidant activity. However, results show that it is very likely that compounds other than nordihydroguaiaretic acid could be involved in the antioxidant activity of the extract. Since nordihydroguaiaretic acid is nephrotoxic and hepatotoxic agent, it is important to direct efforts toward the potential use of low-nordihydroguaiaretic acid L. divaricata extracts as antioxidant in foods.
Larrea divaricata Cav. está ampliamente distribuida en la Argentina. Se han documentado actividades antitumorales e inmunomoduladoras de los extractos acuosos de sus hojas. En este estudio, la actividad antioxidante del extracto acuoso y un componente, el ácido nordihidroguayarético, se determinaron y compararon mediante diferentes ensayos. Tanto el extracto acuoso como el ácido nordihidroguayarético mostraron actividad antioxidante. Sin embargo, los resultados muestran que es muy probable que otros compuestos diferentes al ácido nordihidroguayarético pudieran estar involucrados en la actividad antioxidante de los extractos. Dado que el ácido nordihidroguayarético es un agente nefrotóxico y hepatotóxico, es importante dirigir los esfuerzos hacia el uso potencial de extractos de L. divaricata con bajas cantidades de ácido nordihidroguayarético como antioxidantes en alimentos.