Secondary metabolites and antioxidant activity of Limonium duriusculum (de Girard) Kuntze extracts

Abstract

No reports are available in literature on phytochemical investigation of chloroform, ethyl acetate and n-butanol soluble parts of the aqueous-MeOH extract of aerial parts of Limonium duriusculum. This report identify from the extracts two new flavanones: 3b,5,6,7,8,3’,4’-heptahydroxyflavanone named duriusculin A (8) slightly contamined by its epimer, 3a,5,6,7,8,3’,4’-heptahydroxyflavanone (less than 10 %), named duriusculin B (9), together with, b-sitosterol (1); apigenin (2); methyl gallate 4-methyl ether (3); 4-O-methylgallic acid (4); methyl gallate (5); vanillic acid (6); pinoresinol (7) and apigenin 7-O-b-D-(6’’-methylglucuronide) (10). The antioxidant properties of the n-butanol extract (BEL) were investigated using three assay systems: (2,2-diphenyl-1-picrylhydrazyl radical scavenging (DPPH), lipid peroxidation (LPO) inhibition, and ferrous ion chelating (FIC) methods. This extract showed significant antioxidant activity in the lipid peroxidation inhibition and the ferrous ion chelating methods compared with standards. Compounds 2 and 10 are strongly accumulated by this plant, more than 1.6 g and 1.1 g per kg of air-dried plant material, respectively.