【作者】 林平；

【导师】 杨磊； 祖元刚；

【作者基本信息】 东北林业大学 ， 植物学， 2008， 硕士

【摘要】 EGCG是茶多酚中的重要组成成分,现已广泛的应用于医药保健、食品添加剂等领域。由于目前生产上EGCG的需求量越来越大,所以对EGCG产品的提取纯化工艺要求也越来越严格。目前在EGCG提取纯化过程中,仍存在着很多的问题,尤其是EGCG与ECG两种强水溶性物质的分离,仍是一个难以解决的问题。在EGCG提取纯化过程中,各种不同影响因素的变化,可能都会对高纯度EGCG的提取纯化产生重大的影响。本文以新鲜的老龄茶叶为原料,采用匀浆萃取及负压空化混旋固液萃取技术对EGCG进行高效的提取,同时进一步采用硅胶柱层析法进行纯化,考察硅胶初始含水量、硅胶粒度、径高比、流速、流动相含水量以及负载量等因素对EGCG纯化过程的影响,从而制备出高纯度EGCG,通过实验,证明了柱层析法纯化的实用性与节能性。本工艺具有流程简单、生产周期短、溶剂用量少、成本低、得率高等优点,是一条值得推广的制备高纯度EGCG新工艺,具有极好的发展前景。通过硅胶柱层析的小试及中间放大试验,建立了如下工艺条件:1.最佳提取工艺新鲜老龄茶叶高温杀青后,常温水匀浆及负压空化混旋固液提取,经组合工艺EGCG提取率为2.514%。2.最佳纯化工艺确定了最佳洗脱剂为乙酸乙酯:石油醚:含水2%的乙酸溶液=7.5:2.5:0.5;最佳硅胶初始含水量为10%;最佳硅胶粒度为200-300目;径高比为1:10时,硅胶柱对样品的分离效果最佳;最佳流速为80mL/min;最佳负载量为1gEGCG/20g硅胶。通过如上工艺的处理,成功的解决了强水溶性物质EGCG和ECG的分离,EGCG成品的纯度达到98.15%,回收率为71.35%,ECG纯度85%以上。更多还原

【Abstract】 The EGCG are the important ingredients in the tea, which have been used widely in medicine care, food additive field and so on. Large numbers of EGCG are needed, so extraction process of the extraction and purification of EGCG have to become more advanced. Many difficult problems aren’t still solved during purification of EGCG. It’s more difficult to separate water-solubility object of EGCG and ECG succedly. at the same time, different experiment conditions can effect on it greatly.Fresh old age tea leaves are used in the experiment. Negative pressure cavitation suspension solid to liquid technology is used to effectively strengthen EGCG extracting. The paper studies on further purify of EGCG by Silica gel column chromatography. The factors effecting on the extraction and purification of EGCG are studied such as initial water content of Silica gel、size of grain、ratio of diameter and height and flow rate、water content of mobile phase、charge number of Silica gel and so on. Finally the high purity of EGCG is obtained. At the same time, Silica gel column chromatography shows its practicability and energy saving. The process for extracting and purifying EGCG is simple, short-cycle and low cost. The technology is valued as a new technology to generalize in producing high-purified EGCG, which can be used in the industrial production in the future.The optimum conditions of experiment and magnifying test were as followed:1. The optimum process of extraction:Fresh old age tea leaves was killed by hot water.The extraction yield of EGCG was 2.514% by Negative pressure cavitation suspension solid to liquid technology.2. The optimum process of purification:Elution solvent was acetic ether: petroleum ether: acetic acid solvent contained water about two percent 7.5: 2.5: 0.5; initial water content of Silica gel was 10%; 200～300 mesh silica gel; ratio of diameter and height was 1:10; flow rate 80mL/min; charge number of Silica gel was 1gEGCG/20g.By the above technology, water-solubility object of EGCG and ECG was separated succeedly. purity of EGCG and ECG was 98.15% and 85% and recovery was 71.35%.更多还原