Abstract

SILVA, D. H. S.; PEREIRA, F. C.; YOSHIDA, M.  and  ZANONI, M. V. B.. Electrochemical evaluation of lipophilic antioxidants from Iryanthera juruensis fruits (Myristicaceae). Eclet. Quím. [online]. 2005, vol.30, n.3, pp. 15-21. ISSN 0100-4670.  http://dx.doi.org/10.1590/S0100-46702005000300002.

TLC autographic assays revealed in the hexane extract of Iryanthera juruensis (Myristicaceae) the presence of two compounds, with antioxidant properties towards b-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 CH₂Cl₂/Bu₄NBF₄ 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 a-tocopherol. The reductive voltametric behaviour of quinone function in both plastoquinones 3 and 4 is discussed.

Keywords : Iryanthera juruensis; antioxidants; cyclic voltammetry; Myristicaceae.