发布时间：2015-04-01 来源：人大经济论坛

制药工程论文范文 目 录 中文摘要I 英文摘要II 目录III 1 绪论1 1.1 前言1 1.2 水翁花2 1.3 抗氧化剂概念及其作用机理2 1.4 常用评价抗氧化活性的方法3 2 实验部分8 2.1 实验材料与方法8 3 结果与讨论11 3.1 超氧阴离子自由基清除法 11 3.2 DPPH自由基清除法12 3.3 羟自由基Fenton反应比色法13 3.4 结论13 总结与展望15 致谢16 参考文献17 摘要:在正常生理情况下，活性氧的产生与清除可维持在一个有利无害的极低水平。活性氧的重要性在过去十年已被日益关注，根据现有的研究报道，活性氧在组织和器官表现出双重性作用，不仅能极力与脂质过氧化,从而导致食品腐烂,而且还能引发一系列疾病，如细胞衰变、致突变、致癌、冠心病、糖尿病、神经退化等。植物中具有许多生物活性如抗衰老、抗氧化、抗癌的化学成分。水翁花中提取得到的两个主要成分，2′,4′-二羟基-6′-甲氧基-3′,5′-二甲基查耳酮以及乌索酸,这2个化合物具有良好的抗氧化活性，因此通过超氧阴离子清除法、DPPH自由基清除法、羟自由基Fenton反应比色法与标准品还原能力比较实验等实验考察这二个化合物的抗氧化活性。 关键字：抗氧化剂；黄酮类化合物；DPPH；活性氧；水翁花 Abstract:Under normal physiological conditions,the production of reactive oxygen species(ROS) can be beneficial and harmless in the relatively low level. The importance of ROS has attracted increasing attention over the past decade. Modern theories of ROS have revealed that ROS play a dual role in organisms. ROS are not only strongly associated with lipid peroxidation, which lead to the deterioration of the food, but also involved in the development of a variety of diseases including cellular aging、mutagenesis、carcinogenesis、coronary heart disease、diabetes and neurodegeneration. Plants have many phytochemicals with various bioactivities,including antioxidant,anti-inflammatory and anticancer activities. The two major components,2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone and ursolic acid isolated from Cleistocaly operculatus,were investigated for their antioxidant activities. Superoxide anion radical scavenging assays,1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and Hydroxyl radicals in Fenton Reaction by colorimetric assay were carried out to eva luate the antioxidant potential of the two compounds. Keywords: Antioxidants; Flavonoids; DPPH; Reactive oxygen species; Cleistocaly operculatus