Three New Polyphenol Derivatives from the Fruits of Macaranga Monandra and their Antioxidant Potential.

Abstract

Phytochemical investigation of the methanol extract from the fruits of Macaranga monandra (Euphorbiaceae Muell. et Arg.) afforded one new geranylated 1',2'-dihydrophenanthrene and two new flavonoid derivatives, named macamondrin (1), macamondrione A (2) and B (3) respectively. The structures of these compounds were elucidated mainly by NMR, mass spectral data and in comparison with data from the literature. Along with compounds 1-3, nine known compounds among which oleanolic acid (4); daucosterol (5); 3β-acetoxy-11α,12α-epoxytaraxerol (6); 3,3',4-tri-O-methylellagic acid (7); 3,3',4,4'-tetra-O-methylellagic acid (8); 4'-O-methyl-6-isoprenylapigenin (9); 4'-O-methyl-8 isoprenylkaempférol (10); 4'-O-methyl-6-isoprénylkaempférol (11); 6-isoprénylkaempférol (12), were also isolated. Crude extracts as well as isolated compounds were evaluated for their antioxidant activity using the ABTS, DPPH and FRAP methods. It appears that the 50 % radical scavenging concentrations ranging from 6.26 to 11.7 μg/ml on the ABTS radical, from 1.77 to 48.22 μg/ml on the DPPH radical, and from 1.54 to 67.97 μg/ml with the FRAP method. For the compounds tested, very good antioxidant activities were observed, which clearly shows that these molecules can have an anti oxidative stress potentiel.