臺灣博碩士論文加值系統

洋蔥含有類黃酮、硫化物及多種維生素和礦物質。許多研究已指出洋蔥具有抗氧化、抗癌等功效，本研究以人體試驗探討洋蔥汁抗氧化及調降血脂之能力。
共計24位膽固醇偏高之健康受試者全程參與，採隨機、平行、雙盲、安慰劑組對照進行。本試驗將受試者分為兩組，受試者每日服用100㏄洋蔥汁或安慰劑飲料。試驗進行11週，試驗前1週為飲食調整期，試驗期為8週，試驗結束後的2週為觀察期，分別在0、2、6、8、10週採集血液檢體，並進行體位測量。結果顯示，飲用洋蔥汁10週後，體重與身體質量指數皆顯著降低；在抗氧化性方面，降低脂質過氧化，而體內總抗氧化力、血漿含硫官能基化合物含量顯著增加。此外，血漿總膽固醇及LDL-膽固醇的含量亦顯著降低，並顯著延長LDL之氧化時間。由本研究可知，每天飲用洋蔥汁可有效降低血脂、增加體內之抗氧化能力，對於心血管疾病可能具有預防之功效。

Onion contains flavonoids, sulfur-containing compounds and a lot of vitamins and minerals. Many studies indicated that onion showed antioxidation and anticarcinogen.This study was focused on the antioxidant capacity and hypolipidemic effects of onion juice.
Twenty-four healthy subjects with board line high serum cholesterol (≧200mg/dL) was involved in the study. This was a randomized, parallel, placebo controlled and double blind design. We randomized subjects into two groups. Each subject drank 100ml of onion juice or placebo every day for continuous eight weeks. The total experimental period was eleven weeks, including one week of run in period, eight weeks of administration and two weeks of follow-up period. Anthropometric measurements, blood collecting were performed at the initial, 2nd, 6th ,8th,10th week of the testing period. After eight weeks of intervention, onion juice greatly decreased serum total cholesterol and low-density lipoprotein cholesterol (LDL-C). In addition, increasing total antioxidant capacity of plasma and longer lag-time of LDL oxidation were found.
In conclusion, drinking onion juice could decrease plasma lipid and increase its antioxidant capacity. So onion juice probably showed benefit to the prevention of cardiovascular disease.

目錄
頁次
表次....................................................Ⅰ
圖次....................................................Ⅱ
附錄....................................................Ⅲ
中文摘要................................................Ⅳ
英文摘要................................................Ⅴ
壹、前言.................................................1
貳、文獻整理.............................................2
一、高血脂與心血管疾病................................2
二、血脂質............................................4
(一)血脂質概述.....................................4
(二)血脂異常的分類與定義...........................7
(三)脂蛋白種類及代謝途徑...........................10
三、洋蔥..............................................13
(一)洋蔥簡介.......................................13
(二)洋蔥組成成分...................................14
(三)洋蔥的功效.....................................16
参、研究目的.............................................22
肆、試驗設計.............................................23
伍、材料與方法...........................................24
一、試驗材料..........................................24
(一)洋蔥汁.........................................24
(二)人體試驗.......................................24
二、試驗用藥..........................................28
三、試驗儀器..........................................30
四、試驗方法..........................................32
(一)洋蔥汁冷凍乾燥物製備...........................32
(二)酚類化合物含量測定.............................32
1.總酚含量......................................32
2.總類黃酮含量..................................32
3.酚類化合物之高效能液相層析....................33
(三)含硫物質含量測定...............................33
1.含硫功能基化合物含量..........................33
(四)抗氧化性測定...................................34
1.總抗氧化能力..................................34
2.還原力........................................35
3.螯合亞鐵離子能力..............................35
(五)血漿抗氧化活性測定.............................35
1.血漿總抗氧化能力..............................35
2.血漿中脂質過氧化物…..........................36
3. 血漿中總酚類化合物含量.......................36
4.血漿中含硫官能基含量..........................37
5.血漿中LDL氧化延滯期..........................38
(六)血清生化分析..................................39
1.三酸甘油脂....................................39
2.總膽固醇......................................40
3. LDL-C........................................41
4. HDL-C........................................42
五、統計分析..........................................43
陸、結果與討論...........................................44
一、酚類化合物分析....................................44
(一)洋蔥汁冷凍乾燥物總酚、總類黃酮測定............44
(二) 洋蔥汁quercetin含量之安定性試驗................44
(三) 洋蔥汁游離態及醣苷鍵結之quercetin組成測定....44
二、洋蔥汁含硫物質含量之分析..........................49
(一) 洋蔥汁含硫官能基化合物含量之安定性試驗.......49
三、洋蔥汁抗氧化性測定................................51
(一)總抗氧化能力..................................51
(二)還原力........................................51
(三)螯合亞鐵能力..................................51
四、人體臨床試驗......................................55
(一) 受試者特性及體位測量.........................55
(二) 受試者血清生化分析...........................55
(三)受試者血漿抗氧化狀態..........................59
柒、結論.................................................68
捌、參考文獻.............................................69
玖、附錄.................................................80

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