Autoxidation Products of Polyunsaturated Galactolipids

Abstract

Neat monogalactosyldilinolenoylglycerol (di-18:3 MGDG) and digalactosyldilinolenoylglycerol (di-18:3 DGDG) were autoxidized at 37°C. The rate of autoxidation of di-18:3 MGDG was greater than that of di-18:3 DGDG. The oxidation products were separated from unoxidized di-18:3 MGDG and di-18:3 DGDG by reverse-phase high performance liquid chromatography (HPLC). The products separated by HPLC were shown to be made up of lipid peroxides formed by free radical oxidation of the linolenate component of the MGDG and DGDG. Each linolenoyl moiety in the MGDG and DGDG produced isomeric peroxides in a manner similar to methyl linolenate.