臺灣茶非消化水溶性多醣之分子特徵

Molecular characterization of indigestible water-Soluble polysaccharides from Taiwan teas

黃炘雯(Xin-Wen Huang)

指導教授 ： 呂廷璋

國立臺灣大學/生物資源暨農學院/食品科技研究所/碩士(2017年)

https://doi.org/10.6342/NTU201602221

摘要

茶是重要的嗜好性飲品，也被視為保健食品，本研究針對臺灣茶中非消化水溶性多醣進行劃分並分析各區分之分子結構特徵。以RAW264.7巨噬細胞株測試其抑制被脂多醣誘導之RAW264.7小鼠巨噬細胞釋放一氧化氮量均顯現能抑制一氧化氮生成量且在作用濃度為 5-100 μg/mL對於 RAW264.7巨噬細胞株後其存活率均有 80%以上，顯示茶多醣對於RAW264.7巨噬細胞株沒有毒殺性。臺灣茶非消化水溶性多醣之單醣組成主要為半乳糖、 阿拉伯糖、鼠里糖、半乳糖醛酸及少量甘露糖，進一步使用甲基化分析其醣苷鍵結，半乳糖基以1, 3、1,4與1, 6 為主要鍵結並有3,4、3, 6 鍵結之分支點; 阿拉伯糖基以1, 5 鍵結為主並有3, 5 鍵結之分支點; 將酸性糖之羧酸基還原後，進行鍵結分析，發現半乳糖醛酸主要以1, 4鍵結存在，鍵結特徵與果膠多醣結構特徵相符。利用陰離子交換層析DEAE管柱，將茶多醣依電荷差異劃分為四個區分，第一個區分 F1 中性醣區分主要由半乳糖及甘露糖構成，利用親和性抗體辨識具有果膠多醣結構中第一型阿拉伯半乳聚醣上的半乳糖 -1, 4 鍵結之抗原表位及半纖維素上的甘露糖 -1, 4 鍵結之抗原表位之特徵; 區分F2 ~ 4均為酸性糖區分，主要均由阿拉伯糖、半乳糖、鼠里糖及半乳糖醛酸所構成，利用親和性抗體辨識區分F2~4均具有第一型阿拉伯半乳聚醣之  形式葡萄糖醛酸鍵結、第二型阿拉伯半乳聚醣1,4--D-半乳聚醣、1,5--L-阿拉伯聚醣鍵結之果膠抗原表位之特徵，在各區分的鍵結分析也看到相符的鍵結特徵顯示茶多醣主要結構特徵為果膠多醣Rhamnogalacturonan type I上接上側支Arabinan、Arabinogalactan type I及Arabinogalactan type II。

關鍵字

臺灣茶 ； 非消化水溶性多醣 ； 鍵結分析 ； 單株抗體

並列摘要

Tea is a kind of important soft drinks and it has been recognized as a kind of healthy drinks. Our research use Taiwan tea as our material and analyze its indigestible water-soluble polysaccharides (IDPS) molecular characterization. Under 100 μg/mL, the Taiwan tea polysaccahrides showed withoutt cell toxicity. Moreover, it can inhibit LPS induced RAW264.7 nitrite releasing. The main monosaccharides composition in Taiwan tea IDPS are galactose, arabinose, rhamnose and galacturonic acid. The main linkages in Taiwan tea IDPS are 1,3-galactose, 1,4-galactose and 1,6-galactose and the branch points are 3,4- galactose, 3,6 galactose. After the carbonyl group of uronic acid in Taiwan tea IDPS is reduced, galacturonic acid is showed in 1,4 linkage. It is separated by DEAE column into four fractions. F1, the neutral polysaccharides, is mainly composed in galactose and mannose. The result of F1 polysaccharides, analyzed by the affinity antibody, showed that there are β- 1,4-galactose and β-1,4-mannose. F2-4 fraction are composed of uronic acid, arabinose and galacturonic acid. After the F2-4 polysaccharides analyzed by the affinity antibody, the result showed that there are β- galacturonic acid and β-1,4-galactose and 1,5-α-arabinose. Each fraction linkage analysis is also show pectin polysaccharides characterization. As a result, Taiwan tea polysaccharides has rhamnogalacturonan and its branches, arabinan, arabinogalactan type one and arabinogalactan type two.

並列關鍵字

Taiwan teas ； indigestible water-soluble polysaccharides ； linkage analysis ； monoclonal antibody

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