| Free radicals and reactive oxygen species (ROS) are more and more close to human being’ s health, so antioxidant capacity evaluation become one of the hot focuses concerned by researcher. Based on the review of various methods of valuating antioxidant ability in recent years, the paper not only study the antioxidant capacity of (3-(3,4-Dihydroxy phenyl)-α-hydroxylpropionic acid borneol ester (DBZ and IDHP), which is new chemical medicine of curing heart head blood-vessel as well as its serial compounds, but also determine DBZ by building a new flow injection chemiluminescence (CL) method. In addition, one novel chemiluminescence method is developed to evaluate antioxidant activity of many complex samples such as fruit and vegetable juice. The study is meaningful to evaluate antioxidant capacity of plants, foods and medicines. Moreover, these studies expand the research content in the field of CL studies and enrich antioxidant evaluation theories. This thesis has three chapters. The main contents as follows:1. Based on a summary of the progress of antioxidant capacity evaluation, the first chapter mainly introduces the research contents and significance.2. By using a simple chemiluminescence method coupled with flow-injection analysis, the antioxidant activity of DBZ and IDHP in vitro were studied. Namely, their ability of scavenging ROS (superoxide anion radical O2·-, hydroxyl radical·OH and hydrogen peroxide H2O2) were investigated respectively. Furthermore, compared to ascorbic acid and rutin, the result indicated that they possessed stronger antioxidant capacity and could effectively scavenge ROS.3. A novel method based on DBZ could observably inhibit the chemiluminescence of Luminol-Potassium Permanganate system in alkaline medium was designed to determine DBZ. The relative CL signal responded linearly to the concentration of DBZ in the range 2.0×10-10-2.0×10-8g/mL. The detection limit of this method was7.0×10-11g/mL DBZ with the relative standard deviation (R.S.D.) of3.8%for4.0×10-9g/mL DBZ (n=11). The proposed method showed characteristics of high sensitivity, simple device and quick. In addition, this proposed method had been applied satisfactorily to the analysis of DBZ in blood.4. In this study, we established a new method of evaluating the total antioxidant capacity combined with flow injection technology, according to the sensitization effect of HRP which is on luminol-H2O2-buffer solution chemiluminescence system and the catalytic oxidation of H2O2which can form other ROS. We standardized the total antioxidant capacity of samples by using trolox and uric acid which possess good antioxidant ability as standards. Meanwhile, we discussed the stability of method and the proposed method had been evaluated the total antioxidant capacity of four kinds of fruity and vegetable juice (fresh aloe vera juice, actinidia deliciosa juice, cucumber juice and banana juice). Compared to the aloe vera with computer radiation, the antioxidant activity of the aloe vera what is not radiated is more stong. Under the same concentration, aloe vera juice’s antioxidant capacity is almost twice as much as cucumber juice’s. At the same time, the antioxidant activity of banana juice and actinidia deliciosa juice are compared with the same concentration, the latter is much sronger than the former. The results indicated that this method had good reproducibility, broader linear range and ultrafast. |
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