Structural Determination of Acylated Flavonol Glycosides in Seven Taiwan Tea Cultivars

臺灣茶的名聲響譽國際，除了精湛的製茶技術，其獨特的地形與適宜的氣候，發展出多樣的適栽茶種，常見茶種有青心烏龍、四季春、臺茶12號等，各茶種獨有的風味，造就韻味萬千的臺灣茶。眾多的研究指出，茶具有許多保健功效，其中本實驗室先前研究發現在青心烏龍中有特殊醯化黃酮醇配醣體結構化合物，可促進腸胃蠕動並造成飢餓感，經過實驗證明可與飢餓素接受器結合，仿效飢餓素誘導的分子機制，達到腸胃蠕動、促進生長激素分泌的生理活性，並將其命名為茶飢素，期望能發展為改善生長激素分泌相關疾病之藥物。本試驗目的為分析臺灣地區常見茶種，希望能從中找尋活性類似或更勝茶飢素之化合物。由茶業改良場及茶農提供臺灣常見七種茶種毛茶進行分析，經由液相層析串聯質譜儀分析，化學結構斷裂片段類似茶飢素，具有146 Da(鼠李糖基團或香豆酸基團)，並從斷裂碎片300 Da及285 Da推測黃酮類主結構分別為槲皮素與山柰酚，推測皆為類茶飢素化合物，將進一步進行結構鑑定。由於結構鑑定需蒐集足夠量之化合物，因此建立類茶飢素化合物純化平台，首先以沸騰去離子水進行萃取，使用styrene-divinylbenzene (ST-DVB)及Sephadex LH-20進行管柱純化，用高效能液相層析儀及薄層層析法進行回收，再次使用Sephadex LH-20管柱純化去除殘留酸，最後以核磁共振儀鑑定結構。Taiwan has been well known as one of the regions to produce tea. Due to unique terrain and salubrious climate, Taiwan has a suitable environment for various cultivars. There are several tea cultivars in Taiwan, including Chin Shin Oolong, Shy Jih Chuen, Taiwan Tea Experiment Station (TTES) No.12, etc. According to previous study from our lab, we discovered unique acylated flavonol tetraglycosides in Chin Shin Oolong, which could improve gastrointestinal emptying and induce hunger. These compounds could bind to the ghrelin receptor and trigger physiological responses via the same molecular mechanism as ghrelin. Due to these similar responses, these compounds were named Teaghrelins. Teaghrelins show high potential in developing treatment of growth hormone deficiency. My research goal is to find out Teaghrelin-similar compounds in seven Taiwan tea cultivars. In this study, tea samples were analyzed through liquid chromatography tandem mass spectrometer (LC-MS/MS). From total ion chromatogram (TIC) and MS/MS fingerprint, many analogous have been discovered. Molecule weights at 1064, 1048, 1050 and 1034 Da were identified. These ions were further dissociate through collision (MS/MS). Ions contained 146 Da (rhamnosyl and coumaroyl group) fragment with aglycones, quercetin (302 Da) and kaempferol (286 Da) were identified. According to the results mentioned above, these compounds were presumed as Teaghrelin-similar compounds. In order to prepare pure samples for structural derermination by NMR, a purification platform was constructed. By water extraction, styrene-divinylbenzene (ST-DVB) and Sephadex LH-20 column, fractions contained Teaghrelin-similiar compounds (TSCs) were acquired. The fractions were separated and collected by High-performance liquid chromatography (HPLC) system and Thin layer chromatography (TLC). Finally, used Sephadex LH-20 column remove the residue acid and recover the pure compound.目錄 中文摘要................................................i Abstract...............................................ii 目錄..................................................iii 圖目錄.................................................iv 表目錄..................................................v 第一章 前言.............................................1 第二章 文獻回顧.........................................3 第一節 茶葉介紹.........................................3 一、臺灣常見茶種.........................................3 二、茶葉加工過程.........................................5 三、茶葉分類.............................................7 四、茶葉化學成分.........................................8 五、茶葉健康功效........................................11 第二節 茶飢素..........................................13 一、緣起與發現..........................................13 二、相關文獻及發展......................................14 第三章 材料與方法......................................17 第一節 茶葉樣品........................................17 第二節 試驗方法........................................17 一、液相層析樣品處理及方法...............................17 二、串聯質譜儀樣品處理與分析方法..........................18 三、萃取醯化黃酮醇配糖體化合物及核磁共振鑑定結構...........19 第三節 試驗試劑與儀器設備...............................20 一、試驗試劑與材料......................................20 二、儀器設備............................................21 第四章 結果............................................23 第一節 不同茶樣HPLC分析結果.............................23 第二節 串聯質譜儀分析結果...............................24 第三節 萃取類茶飢素化合物與核磁共振儀分析化合物結構........25 第五章 討論............................................33 第六章 圖表............................................36 第七章 參考文獻........................................76 圖目錄 圖1. 46個不同茶樣HPLC分析圖.............................36 圖2. 46個不同茶樣HPLC分析圖(30-45 min)..................42 圖3. 利用液相串聯質譜分析類茶飢素化合物質譜圖.............48 圖4. 利用薄層層析法純化類茶飢素化合物....................49 圖5. TSC1之化學結構....................................50 圖6. TSC1之1H-NMR光譜..................................50 圖7. TSC1之13C及DEPT-135光譜...........................51 圖8. TSC1之COSY光譜....................................51 圖9. TSC1之NOESY光譜...................................52 圖10. TSC1之HMQC光譜...................................52 圖11. TSC1之HMBC光譜...................................53 圖12. TSC1之HMBC光譜局部放大圖及3J-HMBC correlation(1) .......................................................54 圖13. TSC1之HMBC光譜局部放大圖及3J-HMBC correlations(2) .......................................................55 圖14. TSC1之HMBC光譜局部放大圖及3J-HMBC correlations(3) .......................................................56 圖15. TSC1之HMBC光譜局部放大圖及3J-HMBC correlation(4) .......................................................57 圖16. TSC2之化學結構....................................58 圖17. TSC2之1H-NMR光譜..................................58 圖18. TSC2之13C及DEPT-135之光譜.........................59 圖19. TSC2之COSY光譜....................................59 圖20. TSC2之NOESY之光譜.................................60 圖21. TSC2之HMQC光譜....................................60 圖22. TSC2之HMBC及3J-HMBC correlations.................61 圖23. TSC3之化學結構....................................62 圖24. TSC3之1H-NMR光譜..................................62 圖25. TSC4之化學結構....................................63 圖26. TSC4之1H-NMR光譜..................................63 圖27. TSC4之13C及DEPT-135光譜...........................64 圖28. TSC4之COSY光譜....................................64 圖29. TSC4之NOESY光譜及NOE效應..........................65 圖30. TSC4之HMQC光譜...................................66 圖31. TSC4之HMBC光譜...................................66 附圖1. 青心烏龍HPLC分析圖譜及茶飢素化合物結構.............70 附圖2. GHRP-6、茶飢素-1及-2與飢餓素接受器分子對位模擬 .......................................................71 附圖3. 茶飢素中間產物與飢餓素接受器分子對位模擬............72 附圖4. 類茶飢素化合物與飢餓素接受器分子對位模擬............73 表目錄 表1. 茶葉樣品清單.......................................67 表2. 茶飢素及類茶飢素化合物與茶種關係表...................68 表3. 質譜分析類茶飢素化合物..............................69 附表1. 臺灣主要茶樹栽種面積(茶業改良場提供)...............74 附表2. 質譜鑑定茶飢素、茶飢素中間產物及類茶飢素化合物 .......................................................7