| Tea extract which contains tea polyphenols as the active ingredient, has a unique antioxidant and anti-lipid peroxidation performance. As tea polyphenols with polyphenol hydroxyl which is large polar substances, soluble in water, difficult to dissolve oil, it restricted the use in oil products and to play a good role in physiological activity. In addition, as tea polyphenols have a strong bitter taste and isn't stable in process, particularly in the alkaline environment, easily oxidized, and lose its unique anti-oxidation, restricted their widely use in food process. Furthermore, due to its strong water-soluble, tea polyphenols is difficult in vivo absorption and utilization, and greatly reduces its unique activity bioavailability. Phospholipids are the basic ingredients of the cell membrane, nuclear membrane and the lipid membrane in animal and plant cells, and also the composition of nerve cells. It can protect and increase the nutrition of the nerve cells and speed up delivery of its exciting role, and can repair damaged brain cells and nerve ensheathing cells. Natural active ingredients of natural phospholipid complex which compound the natural active ingredient with phospholipid in certain conditions can effectively improve its vivo absorption and significantly improve its bioavailability. Through the tea extract embedded phospholipid, it changes the physical and chemical properties of tea extract and maintains or enhances their oxidation resistance in different environment. So it expands the application of tea extracts and enhances the role in some environment.Because the damage of lipid peroxidization is becoming more and more known, chemiluminescence analysis is valued day by day as an important measurement of lipid peroxidization. There are two objectives of the experiment. The first aim is to establish a fairly stable emulsified system of chemiluminescence analysis. The second purpose is to investigate the properties of a few antioxidants. Two important factors, the pH and the phase of the measured system are studied. Combined these to the past achievements, a stable measurement system is primarily built up,that is,the lecithin as the emulsification, liquid tiny bag as the phase of system, PH9.2, 20 times as the measurement number and suitable concentration of the sample and the reagents. Moreover, in the experiment two kinds of methods are used namely the chemiluminescence analysis and the POV analysis to investigate and compare the antioxidant properties of LTP,TBHQ, rosemary and Ascorbic acid-6 palmitate, in the normal temperature and after heating for 4 hour at 98℃. At the same time, the two methods are also compared.Oxygen radical absorbance capacity (ORAC) is a popular anti-oxidation method now. Through the existing methodology of the research, we design a constant fluorescence detector with simple operation. It uses the worse of the curve area of fluorescence recession under the anti-oxidants and natural condition as a measure of antioxidant antioxidant capacity indicators. The results show by standard antioxidants. Through the comparison of several key reagents and inspection of the linear relationship, we determine the choice of fluorescence, free radical generating agent, antioxidant substances, as well as the standard buffer system. The establishment of experimental methods provides a new research direction for the study of the antioxidant.
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