Free Radical Scavenging Activity of Kielmeyera variabilis (Clusiaceae)

Molecules

Aline Coqueiro¹  Luis Octávio Regasini¹  Scheila Cristina Gutkoski Skrzek¹  Marcos Mar๺l Ferreira Queiroz¹  Dulce Helena Siqueira Silva¹ 

[1] Department of Organic Chemistry, Institute of Chemistry, São Paulo State University, Araraquara 14800-900, Brazil;

关键词: Kielmeyera variabilis;    Clusiaceae;    antioxidant;    free radical scavenging activity;    DPPH^•;    ABTS^•+;    flavonoid;    flavonol;   

DOI  :  10.3390/molecules18022376

来源: mdpi

【 摘 要 】

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-β-glucoside (3), and quercetin-3-O-β-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.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.