Flavonoids and antioxidant potential of nine Argentinian species of Croton (Euphorbiaceae)

Abstract

Croton is a large genus of Euphorbiaceae and many of its species are used medicinally. This study was performed to analyze the flavonoid composition and the antioxidant potential of hydroalcoholic extracts of nine Argentinian species of Croton: C. andinus Mull. Arg.; C. argentinus Mull. Arg.; C. catamarcensis Ahumada; C. cordobensis Ahumada; C. curiosus Croizat; C. lachnostachyus Baill.; C. lanatus Lam. var. lorentzii (Mull. Arg.) P.E. Berry; C. saltensis Griseb.; and C. serratifolius Baill. Few investigations studying the analyses of flavonoid glycosides in Croton have been carried out. The hydroalcoholic extracts (80 % methanol) from leaves were analyzed by high-performance liquid chromatography–mass spectrometry. The antioxidant activity was analyzed by the 1,1-diphenyl-2-picryl-hidrasil, Sigma (DPPH), ferric reducing antioxidant potential (FRAP), and Folin–Ciocalteu methods. O-Glycosides of flavonols (kaempferol, quercetin, and isorhamnetin) and flavones (apigenin) were ubiquitous in the analyzed samples. Rutin was frequent and predominant, especially in Adenophylli section. Acylglycosides of either quercetin or kaempferol (tiliroside) were detected in most samples. C. argentinus and C. serratifolius were the species with the highest antioxidant capacity and the highest total content in proanthocyanidins and total phenols together. Significant degree (P < 0.05) of correlation was found between relative abundances of total phenols, proanthocyanidins, and quercetin derivatives, with FRAP and DPPH. Principal Component analysis showed a close affinity among Adenophylli species.