臺灣博碩士論文加值系統

秋葵，錦葵科(Malvaceae)、秋葵屬(Abelmoschus)，原產非洲東北部衣索比亞、埃及及加勒比海一帶或熱帶亞洲，台灣產地分布在彰化、雲林、嘉義等縣境內。文獻指出，秋葵具有抗腫瘤癌症、抗氧化、抑菌性、抗過敏、降血糖以及降膽固醇等生理活性。目前已分離出的秋葵多酚類化合物，包括兒茶素(Catechin)、沒食子兒茶素(Epigallocatechin)、東茛萣素(Scopoletin) 、槲皮素(Quercetin)、楊梅黃酮(Myricetin)、異鼠李素(Isorhamnetin)、山柰酚(Kaempferol)等。本研究利用市場所販售之秋葵，乾燥後均質粉碎，以甲醇進行索式萃取，將萃取液減壓濃縮後以水回溶，再以n-Hexane進行萃取，分為Hexane層(HL)及水層。水層使用HP-20進行吸附，再分為HP-20不吸附(NA)與HP-20吸附(BA)兩類。HL、NA及BA在秋葵粉末中含量分別為(w/w)：3.29±0.77%、17.64±2.61%及0.92±0.34%。BA再一次以HP-20吸附並以50% Methanol脫附之fraction (BAF-5)，透過LH-20以及半製備HPLC純化，從中得到BAC-1成分。經由MS測定BAC-1，推測其結構可能為Quercetin-hexose。而生物活性實驗中發現，抗氧化能力以BA為最佳，濃度在400 g/mL時之DPPH清除率為60.89±3.38%；降血糖活性測試，以HL對於-glucosidase有極顯著抑制的效果，濃度在50 g/mL時抑制率可達81.55±3.60%，且HL也表現出與PPAR-有親合度之效果，濃度在100 mg/mL時，親合度為16.24±1.84%，BA對於-glucosidase也有抑制效果(11.57±1.14%)，但濃度須達到400 mg/mL以上，NA則在生物活性表現上皆不顯著。

Okra (Abelmoschus esculentus L. Moench) is originally from Ethiopia, Egypt, Caribbean, and tropical Asia. In Taiwan, it is found mainly in Changhua, Yunlin, and Chiayi County. Okra has an anti-tumor cancer, antioxidant, antibacterial, anti-allergy, blood sugar/cholesterol lowering, and other Bioactivity. The polyphenolic compounds predominate in Okra namely, catechin, epigallocatechin, scopoletin, quercetin, myricetin, isorhamnetin, and kaempferol. In this study, the dried okra was homogenized and pulverized sample was extracted with methanol using a Soxhlet. The concentrated extract was then evaporated under reduced pressure. The sample was resuspended in water and further extract with n-hexane. The hexane layer (HL) and the aqueous layer with HP-20 nonadsorption fraction (NA) and HP-20 adsorption fraction (BA) were obtained. The content (w/w) in the okra for HL, NA, and BA were 3.29±0.77%, 17.64±2.61% and 0.92±0.34%, respectively. The BA fraction was readsorption by HP-20 and desorption with 50% methanol (BAF-5), followed by LH-20, and semi-preparative HPLC purification. Ultimately, a pure fraction was obtained (BAC-1) from BAF-5. The BAC-1 could be a Quercetin-hexose as estimated from MS analysis. Furthermore, the BA exhibited the best antioxidant capacity for DPPH free radical. The scavenging activity was found to be 60.89±3.38% at 400 g/mL level. The HL, on the other hand, revealed a significant hypoglycemic activity as a resulted from -glucosidase inhibitory assay (81.55±3.60%) at a concentration of 50 g/mL. The HL also demonstrated a PPAR- affinity (16.24±1.84%) at a concentration of 100 g/mL. In addition, BA also observed a -glucosidase inhibitory efficiency (11.57±1.14%), as the concentration over 400 mg/mL. The NA has no any significant activity from above tests.

書名頁
摘要 I
Abstract III
誌謝 V
目錄 VIII
表目錄 XI
圖目錄 XII
第一章 緒論 1
1-1 前言 1
1-2 研究目的 3
第二章 文獻回顧 4
2-1 秋葵 4
2-1.1 秋葵簡介 4
2-1.2 秋葵植物型態與品種分類 6
2-1.3 秋葵之生物活性 9
2-1.4 秋葵之化合物 13
2-2 糖尿病(Diabetes mellitus) 19
2-2.1 糖尿病簡介 19
2-2.2 胰島素抗阻與自由基 22
2-2.3 治療糖尿病之藥物與機制 23
第三章 秋葵成份之分離與純化 35
3-1 前言 35
3-2 材料與方法 36
3-2.1 實驗材料與設備 36
3-2.2.1 樣品前處理與萃取 37
3-2.2.2 BA成份分離純化與結構鑑定 39
3-3 結果與討論 43
3-3.1 樣品前處理 43
3-3.2 BA成份分離純化與結構鑑定 46
3-4 結論 55
第四章 秋葵生物活性試驗 56
4-1 前言 56
4-2 材料與方法 58
4-2.1 實驗材料與設備 58
4-2.2 清除DPPH自由基能力測定 59
4-2.3 抑制α-amylase能力測定 60
4-2.4 抑制α-glucosidase能力測定 61
4-2.5 PPAR-γ親合度分析 62
4-3 結果與討論 63
4-3.1 清除DPPH自由基能力 63
4-3.2 抑制α-amylase及α-glucosidase能力測定 65
4-3.3 PPAR-γ親合度分析 69
4-4 結論 72
第五章 結論與未來展望 73
參考文獻 74
作者經歷 82

表2-1 秋葵營養成份 5
表2-2 秋葵之生物活性 10
表2-3 降血糖的藥物種類及其結構 25

圖1-1 2012年國人十大死因 2
圖2-1 秋葵全株 7
圖2-2 秋葵揮發性化合物 14
圖2-3 東茛萣素之結構 15
圖2-4 秋葵中所分離出之類黃酮化合物 17
圖2-5 秋葵中所分離出來之類黃酮糖苷 18
圖2-6 肥胖與胰島素抗阻之關係 24
圖2-7 磺醯尿素類藥物之作用機制 29
圖2-8 Metformin藥物之作用機制 31
圖2-9 Acarbose經由酵素水解成Component-I以及II 32
圖2-10 TZD藥物之作用機制 34
圖3-1 秋葵粉末之製備 38
圖3-2 HL、NA及BA之製備 40
圖3-3 分離純化之管柱 41
圖3-4 秋葵粉末中HL、NA以及BA之含量 44
圖3-5 (A) HL、NA以及BA經由UV (365 nm)照射所呈現之顏色 (B) NA濃縮物之外觀 45
圖3-6 秋葵成份分離純化之流程圖 47
圖3-7 BA中BAF-X所佔之含量 48
圖3-8 BAF5之LC層析圖 49
圖3-9 BAF-5.1與BAF-5.2之HPLC層析圖 50
圖3-10 BAF-5.2之半製備HPLC層析圖 51
圖3-11 BAC-1之UV圖譜 52
圖3-12 BAC-1之ESI-MS圖譜 53
圖3-13 BAC-1之ESI-MS/MS圖譜 54
圖4-1 測定HL、NA及BA在不同濃度下清除DPPH自由基能力 64
圖4-2 測定HL、NA及BA在不同濃度下抑制α-amylase能力 66
圖4-3 測定HL、NA及BA在不同濃度下抑制α-glucosidase能力 67
圖4-4 不同濃度Rosiglitazone與PPAR-γ親合度分析 70
圖4-5 測定HL、NA及BA在不同濃度與PPAR-γ親合度分析 71

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