Electrochemical evaluation of lipophilic antioxidants from Iryanthera juruensis fruits (Myristicaceae)

Abstract

TLC autographic assays revealed in the hexane extract of Iryanthera juruensis (Myristicaceae) the presence of two compounds, with antioxidant properties towards β-carotene. They were isolated and identified as 3-methyl-sargachromenol (1) and sargachromenol (2). Further investigation of the hexane extract led to isolations of 3-methyl-sargaquinoic acid (3) and sargaquinoic acid (4). The electrochemical behaviour of these compounds was studied in CH 2 Cl 2 /Bu 4 NBF 4 at glassy carbon electrode. The phenolic group in both tocotrienols 1 and 2 are oxidized at +0.23V and +0.32V and their oxidation potentials are correlated with the observed antioxidant activities and oxidation mechanism of α-tocopherol. The reductive voltametric behaviour of quinone function in both plastoquinones 3 and 4 is discussed.