Effects of Vitamin E and Volatile Oils on the Susceptibility of Low-Density Lipoprotein to Oxidative Modification

Antioxidant consumption has been reported to be inversely associated with the incidence of coronary artery disease. To clarify the possible role of vitamin E and volatile oils in the prevention of atherosclerosis, the effects of these compounds on the susceptibility of low-density lipoprotein (LDL) to oxidative modification were investigated. In this study, vitamin E and seven volatile oils “anethol, eugenol, geraniol, limonene, linalool, pulegone and thymol” were added to plasma and incubated at 37°C for 3 h. The LDL fraction was separated by ultracentrifugation and the oxidizability of LDL was estimated by measuring conjugated diene (CD), lipid peroxides and thiobarbituric acid-reactive substances (TBARS) after cupric sulfate solution was added. The data show that vitamin E, thymol and eugenol significantly and dose-dependently prolonged the lag time before initiation of oxidation reaction (P thymol > eugenol > geraniol > linalool > limonene > anethol > pulegone. These data clearly show that LDL exposed to vitamin E and volatile oils in vitro reduces oxidizability therefore have favorable effects in ameliorating atherosclerosis