【作者】 王东青；

【导师】 张裕卿；

【作者基本信息】 天津大学 ， 化学工程， 2006， 硕士

【摘要】 天然药物是现代新药发现的重要源泉,对天然药物进行化学与生物学活性研究,发现具有开发前景的结构新类型作为先导化合物,利用适当的分离纯化手段,将其提取出来,进行结构修饰和优化以发现新药,成为目前制备合成药物和中药一类新药的重要发展方向。利用生物酶催化技术实现天然药物先导化合物的提取和分离是一项新兴的技术。植物的细胞壁以及黏液质、果胶、淀粉等杂质是提取有效成分的主要屏障,这些成分影响植物细胞中活性成分的浸出,如果选用恰当的酶,通过酶催化反应使这些杂质成分水解或降解,则可加速有效成分的释放提取。本文选用根茎类植物的典型代表——盾叶薯蓣作为研究对象,考察在提取盾叶薯蓣有效成分—薯蓣皂苷元的过程中,多种生物酶阶梯分步加入的工艺条件及其对产品收率和质量的影响,同时对薯蓣皂苷元生产废液以及废粗纤维渣的综合利用进行了研究,对阶梯生物催化协同提取工艺和其它四种提取工艺作了简要的对比。本文还对酶的催化机制作了初步探讨。利用阶梯生物催化协同提取薯蓣皂苷元技术时,依次加入纤维素酶和果胶酶复合酶制剂、淀粉酶、糖化酶,各种酶的最佳作用条件依次为——纤维素酶和果胶酶复合酶制剂:液用量为1.0‰(1g原料加0.001mL的酶液),作用时间为2h,反应温度为50℃,反应液pH值为6.0;淀粉酶:液用量为1.5‰,反应温度为75℃,反应液pH值为5.5,其催化终点根据碘试剂的显色反应来确定,当碘试剂遇反应液不再显蓝色时视为终点;糖化酶:液用量为1.0‰,作用时间为2h,反应温度为60℃,反应液pH值为5.5。薯蓣皂苷元的生产废液经过中和、活性炭脱色、浓缩、结晶等工序后,可以提取出葡萄糖;薯蓣粗纤维渣可以采用乙醇-水的有机溶媒体系,以氢氧化钠为碱化剂,一氯乙酸为醚化剂来制取CMC。与其它四种工艺相比,阶梯生物催化协同提取工艺产品收率最高,达到2.79%;该工艺能够将薯蓣植物中98%的薯蓣皂苷元提取出来,所得皂苷元产品与标准品的红外谱图像吻合,经HPLC测定纯度达95%以上,熔点为202℃-204℃,符合陕西省优级品标准。本文说明生物酶技术在天然药物有效成分的提取中具有广阔的发展前景。更多还原

【Abstract】 Natural products are the significant source of new medicine nowadays. The chemical and biological properties of natural products are studied in order to find lead compounds with great prospect, which structure can be modified after separation and purification. It is an important means of developing new medicine.It is a new technology to extract and separate active constituents from natural plants with enzyme catalysis. Cell walls,pectin,starch and others are common impurities in plants, which do harm to the extraction of effective constituents. If proper enzymes are employed to act on natural plants, the impurities above can be decomposed, which is of great advantage to the extraction of effective ones.Dioscorea zingiberensis C. H. Wright, a typical medical plant, was chosen to be studied in the paper. The process conditions of stepwise enzyme catalysis as well as the influence of it on the yield and melting point of diosgenin were studied. Meanwhile, the reuse of waste liquor and residue in production process was discussed. In the paper, comparison of this method and others was also made according to the yield and melting point of product. The mechanism of enzyme catalysis was done some research on here.Cellulase and pectinase compound, amylase and diastatic enzyme were added in order in the method of stepwise enzyme catalysis, and their optimum conditions respectively were: dose 1‰, 1.5‰, 1‰, temperature 50℃, 75℃, 60℃, pH6.0, 5.5, 5.5. The reaction time of cellulase and pectinase compound and diastatic enzyme was 2h and 6h. But that of amylase was determined by color reaction of iodine, which meant end point when iodine didn’t turn blue.Glucose could be extracted from waste liquor after treatment of neutralization, decolorization of activated carbon, condensation and crystallization. Coarse fabric of the plant could be made into CMC-an important chemical with wide use, after being alkalified and etherifed.Compared with other methods, it can improve the yield and quality with less energy consumption. 98% diosgenin from plants is extracted. IR spectrum of the product is in accordance with that of the standard, the purity of it is more than 95% according to its HPLC chromatogram, and its melting point is 202~204℃, which reaches the first - grade standard.更多还原