Development and Application of Quantitative Evaluation System for Oxidative Damage of Lipids

点击翻译按钮获取中文摘要

Lipids in oil products and foods are continuously damaged by aerobic oxygen and light. This results in quality deterioration and causes safety problems. Consequently, to inhibit such oxidation and to evaluate oxidative damage are of prime importance. The objective of this research is to develop a method by which the extent of oxidation of oils and lipids can be measured with high specificity, sensitivity, speed, and simplicity. It has been also aimed at developing and evaluating novel antioxidants which can effectively inhibit such oxidation. Lipid peroxidation products from fatty acids, phosphatidylcholines and cholesteryl esters were quantified regio-, stereo- and optical-specifically with a high performance liquid chromatography (HPLC) equipped with UV and chemiluminescence detector. The quantitative analyses have been successfully applied to oils, micelles, liposomes, lipoproteins, plasma and cells. This enabled us to distinguish and identify the active oxidants and mechanisms involved in lipid peroxidations. Furthermore, cholesterol esters were analyzed for different classes of fatty acids. Diphenylpyrenylphosphine (DPPP) was used to develop a ultra-sensitive analytical method. DPPP oxide formed stoichiometrically by the reaction of DPPP and lipid peroxides was analyzed and applied to the quantification of lipid peroxides. It was confirmed by this method that the location of lipid peroxides in the cells could be visualized with a conforcal fluorescence microscope. This method could be quite promising for further application and development. The antioxidant capacities of various compounds were evaluated from the lipid peroxides measured by the above methods and a potential novel antioxidant is now being developed.