臺灣博碩士論文加值系統

生物體過多的活性氧系(ROS:．OH、O2．—、H2O2、RO．etc)堆積將導致氧化性傷害，此一過程與發炎、癌症或退行性疾病有密切關係，且近年來陸續有許多報告提出：抗氧化天然物或藥物在保健上扮演一重要角色。已知含有4-Phenylcoumarin衍生物之豆科降香檀(Dalbergia odorifera Chen)具有鎮靜、鎮痛、抗惊；抑制血小板凝聚、抗瘀血、抗炎和降血脂等作用，但其作用機制尚不清楚，所以本研究在於探討經由合成4-Phenylcoumarin所獲得之七種衍生物中，在抗氧化和抗癌活性上之影響。首先由實驗發現4-Phenylcoumarin衍生物中：DHCO、DHPC能有效捕捉DPPH (1,1-Diphenyl-2-picrylhydrazyl radical)，其EC50分別為5.8和7.5 M。進一步的以t-BHP誘發鼠肝細胞氧化性傷害之模式，進行DHCO和DHPC之抗氧化活性分析，實驗顯示培養基中LDH、ALT和AST等酵素含量、肝細胞脂質過氧化產物MDA的上升及GSH因t-BHP的代謝消耗而降低，均能顯著地被DHCO和DHPC (100M)所抑制。另以SNP誘發巨噬細胞過氧化作用為模式進行實驗，也顯示了DHCO能抑制經由SNP所誘導巨噬細胞過氧化作用。
以上結果證明：4-Phenylcoumarin衍生物能經由捕捉自由基的能力，來抑制由t-BHP或SNP誘導的氧化壓力所造成之細胞損傷。
關鍵字：4-Phenylcoumarin衍生物、降香檀、抗氧化作用

目　　錄---------------------------------------------------- 1
縮 寫 表---------------------------------------------------- 3
中文摘要---------------------------------------------------- 4
英文摘要---------------------------------------------------- 5
壹、前　　言------------------------------------------------ 6
貳、研究動機----------------------------------------------- 15
參、材料與方法
一、化學試劑----------------------------------------------- 16
二、器　　材----------------------------------------------- 18
三、儀　　器----------------------------------------------- 19
四、實驗方法----------------------------------------------- 20
肆、結　　果----------------------------------------------- 30
伍、討　　論----------------------------------------------- 37
陸、參考文獻----------------------------------------------- 43
柒、圖 、 表----------------------------------------------- 54

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