Prooxidant activity of lutein and its dimyristate esters in corn triacylglyceride

For the purpose of comparing the characteristics and utilities of carotenoid fatty acid esters (CFAEs) with their free forms, the pro-oxidant activities of free lutein (FL) and lutein dimyristate (LD), against purified corn-triacylglyceride (TAG), were studied at 40 °C in the dark. FL tended to promote the oxidation of corn-TAG, though at low concentration. The higher the amount of FL added, the higher the oxidation rate of corn-TAG. LD tended to have no significant effect on oxidation of corn-TAG at low concentration, but high concentration of LD promoted the oxidation. The degradation products of FL and LD might involve the cycle of corn-TAG oxidation, resulting in a higher rate than that of the control. Due to the higher stability of LD, the rate of corn-TAG oxidation induced by LD was slower than that by FL.