Isolation and characterization of polyphenols from Euphorbia heterophylla L. (Euphorbiaceae) leaves

Abstract

Many of Euphorbiaceae species are recognized as traditional medicinal plants and the oils and latex of many species have also economic importance. In fact, Euphorbia heterophylla L., belonging to this family and popularly known in Brazil as “leiteira”, “flor-de-poetas” and wild poinsettia, has been used traditionally in Africa and India to treat many kinds of health disorders. However, the chemical composition of this species has been little studied so far. In the present investigation, the flavonoids quercitrin (quercetin 3-O-α-L-rhamnopyranoside), hyperin (quercetin 3-O-β-D-galactopyranoside), isoquercitrin (quercetin 3-O-β-D-glucopyranoside) and isoquercitrin 6”-malonate (quercetin 3-O-β-D-(6”-malonate)-glucopyranoside) were isolated from an ethyl acetate partition of aqueous ketone extract from E. heterophylla leaves. The dehydroellagitannins geraniin and phyllantusiin D as well as 1,2,3,4,6- penta-O-galloyl- β-D-glucopyranoside, caffeic acid  and the coumarin aesculetin (6,7-dihydroxycoumarin) were also isolated. All the compounds were characterized by spectroscopic methods such as 1H and 13C-NMR, COSY, HETCOR, APT and by comparison with literature data. The presence of these substances of relevant bioactivity is reported for the first time in E. heterophylla through our study supporting in this way the medicinal use of this specie.