Otro
Free radical scavenging activity of Kielmeyera variabilis (Clusiaceae)
Registro en:
Molecules, v. 18, n. 2, p. 2376-2385, 2013.
1420-3049
10.3390/molecules18022376
WOS:000315400600076
2-s2.0-84874625375.pdf
2-s2.0-84874625375
Autor
Coqueiro, Aline
Regasini, Luis Octávio
Skrzek, Scheila Cristina Gutkoski
Queiroz, Marcos Marçal Ferreira
Silva, Dulce Helena Siqueira
Bolzani, Vanderlan da Silva
Resumen
As part of our ongoing research on antioxidant agents from Brazilian flora, we screened the free radical scavenging activity of two extracts and eight fractions of Kielmeyera variabilis (Clusiaceae) using DPPH (2,2-diphenyl-1- picrylhydrazyl-hydrate) and ABTS+ [2,2'-azinobis(3- ethylenebenzothiazoline-6-sulfonic acid)] colorimetric assays. The ethyl acetate and n-butanol fractions of the leaves of K. variabilis displayed the strongest activity (IC50 of 3.5 ± 0.3 and 4.4 ± 0.2 μg mL -1 for DPPH and 6.6 ± 0.4 and 3.1 ± 0.1 μg mL -1 for ABTS+, respectively). Chromatographic fractionation of the most potent fractions led to identification of three flavonols with previously described antioxidant activity, quercitrin (1), quercetin-3-O- glucoside (3), and quercetin-3-O-galactoside (4), and of one biflavone, podocarpusflavone A (2). This is the first time that the presence of these flavonoids in Kielmeyera variabilis has been reported. © 2013 by the authors.