Capacidad antioxidante y contenido de polifenoles totales de extractos de tallo de Stevia rebaudiana en varios modelos in vitro.

This paper presents the determination of antioxidant capacity and total polyphenol content in both aqueous and organic extracts of Stevia Rebaudiana stems variety Morita II. The antioxidant capacity was determined through various in vitro assays: Method 2 1,1-diphenylpicryl- hidrazyl (DPPH) assay, discoloration 2,2'-azino-bis-3-ethylbenzthiazoline-6- sulfonic acid (ABTS) assay, ferric ion reducing antioxidant power (FRAP), and total polyphenols by Folin-Ciocalteu. The results were analyzed by Person's correlation. This work was done in order to give added value to the stem of Stevia and their potential use as a source of antioxidant compounds. The results indicate that extracts of Stevia stems grown in Colombia have greater inhibitory activity of free radicals compared to reports in the literature regarding leaf and stem. Therefore it can be concluded that the stems are an accessible source of antioxidants. [ABSTRACT FROM AUTHOR]