Chan Chi Chung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 100-109). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / List of Abbreviations --- p.v / List of Tables --- p.vi / List of Figures --- p.vii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- "Free radicals, oxidative stress and antioxidants" --- p.2 / Chapter 1.1.1 --- Free radical and ROS --- p.2 / Chapter 1.1.2 --- Oxidative stress --- p.6 / Chapter 1.1.3 --- Antioxidants --- p.8 / Chapter 1.2 --- Plant as a source of antioxidants --- p.13 / Chapter 1.2.1 --- Common food sources of antioxidants --- p.13 / Chapter 1.2.2 --- Legume seeds as antioxidant sources --- p.15 / Chapter 1.3 --- Methods used to evaluate the antioxidant activity --- p.16 / Chapter 1.3.1 --- β-carotene bleaching method --- p.17 / Chapter 1.3.2 --- DPPH. scavenging method --- p.17 / Chapter 1.3.3 --- High-performance liquid chromatograph (HPLC) --- p.18 / Chapter 1.3.4 --- Single cell gel electrophoresis (SCGE) --- p.20 / Chapter 1.4 --- Objectives of the study --- p.22 / Chapter 2 --- Materials and Methods --- p.23 / Chapter 2.1 --- Plant materials and chemicals --- p.23 / Chapter 2.2 --- Sample preparation --- p.23 / Chapter 2.3 --- Determination of antioxidant activity using β-carotene bleaching method --- p.24 / Chapter 2.4 --- Evaluation of free radical scavenging ability --- p.26 / Chapter 2.5 --- HPLC separation of seed extract --- p.27 / Chapter 2.6 --- Evaluation of protective effects of legumes on the DNA damage using the comet assay --- p.28 / Chapter 2.6.1 --- Preparation of reagents --- p.28 / Chapter 2.6.2 --- Blood sample --- p.29 / Chapter 2.6.3 --- Hydrogen peroxide (H2O2) treatment --- p.29 / Chapter 2.6.4 --- Ethidium bromide-acridine orange (Et-Ac) viability determination --- p.31 / Chapter 2.6.5 --- Slide preparation --- p.31 / Chapter 2.6.6 --- Alkaline comet assay --- p.31 / Chapter 2.6.7 --- Quantification of DNA damage --- p.33 / Chapter 2.6.8 --- Statistical analysis --- p.33 / Chapter 3 --- Results --- p.40 / Chapter 3.1 --- General description of 24 selected legume seeds --- p.40 / Chapter 3.1 --- Determination of antioxidant activity using β-carotene bleaching method --- p.40 / Chapter 3.2 --- Evaluation of free radical scavenging ability --- p.43 / Chapter 3.3 --- Evaluation of protective effects of legumes on the DNA damage using the comet assay --- p.45 / Chapter 3.3.1 --- Optimal assay conditions --- p.46 / Chapter 3.3.2 --- Protective effects of seed extract and vitamin C --- p.47 / Chapter 3.3.3 --- Effects of heat treatment on the protective effect --- p.48 / Chapter 4 --- Discussion --- p.84 / Chapter 4.1 --- Methanolic extraction --- p.84 / Chapter 4.2 --- Antioxidant activities determined with β-carotene bleaching method and DPPH' scavenging method --- p.84 / Chapter 4.3 --- Evaluation of protective effects of legumes on the DNA damage using the comet assay --- p.93 / Chapter 4.3.1 --- H202-mediated DNA damage --- p.93 / Chapter 4.3.2 --- Protective effects of seed extracts and vitamin C --- p.94 / Chapter 5 --- Conclusion --- p.98 / References --- p.100