摘 要

本文以乙醇水溶液为提取剂，对银杏外种皮中的黄酮苷、黄酮苷元、双黄酮和银杏酸这四种活性物质的提取工艺进行了研究，并对其工艺条件进行了优化。主要工作及探究结果如下：

（1）高速剪切破壁法对于银杏外种皮的提取量与效率远远高于普通的搅拌法。在相同的提取条件下，比较了40%~60%的乙醇溶液和60%丙酮溶液的提取量，发现银杏酸、双黄酮、黄酮苷元的提取量会随着乙醇浓度的升高而升高，而黄酮苷的变化规律与此相反。60%的丙酮水溶液对于黄酮苷的提取效果要优于40%的乙醇水溶液，而对于双黄酮与黄酮苷元的提取效果要优于纯的乙醇。

（2）黄酮苷、黄酮苷元、双黄酮和银杏酸的提取量均随提取时间的增加而升高，提取速率逐渐下降，最后趋近于平衡；温度升高提取效率均有一定升高，其中银杏酸、黄酮苷元、银杏双黄酮随着提取温度的升高提取量升高比较明显，而黄酮苷对于温度升高的变化不明显；随着固液比的升高，银杏酸和黄酮苷元的上升趋势明显，而黄酮苷的提取量上升不明显。当溶剂固液比高于1：10时，提取速率下降明显，提取量上升不明显；随着提取次数的增加，四种活性成分的单次提取量迅速减小，但黄酮苷的单次提取率变化相对较小。银杏外种皮在提取第四次时黄酮苷、黄酮苷元、双黄酮和银杏酸的单次提取量分别为第一次提取量的1.2 % 、1.1% 、2.5%、2.1 %。

（3）以医用酒精为提取剂，通过正交实验得到银杏外种皮中黄酮苷、黄酮苷元、双黄酮和银杏酸的最佳提取条件为：试样与溶剂的固液比为1:10，温度40℃~60℃，提取时间30min，提取次数3次。各提取条件对于黄酮苷、总黄酮的影响为：提取时间gt;提取次数gt;提取温度gt;提取固液比；对于黄酮苷元的影响为：提取时间gt;提取温度gt;提取次数gt;提取固液比；对于双黄酮、银杏酸的影响为：提取次数gt;提取时间gt;提取温度gt;提取固液比。

关键词：银杏外种皮；提取条件；工艺优化；正交试验

Abstract

The extraction of flavonoid glycosides, aglycones, biflavones and ginkgolic acids from Ginkgo escarp was studied and the extraction technology was optimized as well. Ethanol – H₂O severed as the extraction agent. The main work and results were as follows:

(1)The amount and efficiency of extraction from Ginkgo escarp by high speed shear wall breaking method were both higher than stirring solvent extraction method. In the same extractive condition, comparing the amount of extracts by 40%~60% ethanol and 60% acetone, we found that the amount of ginkgolic acids, biflavones and aglycones increased with the level of ethanol, while the acetone was opposite. 60% acetone was better than 40% ethanol in the extraction of flavonoid glycosides, and better than pure ethnol in the extraction of biflavones and aglycones.

(2)With time increasing, the amount of flavonoid glycosides, aglycones, biflavones and ginkgolic acids increased, but the efficiency decreased and finally tended to be stable. Both increased with the temperature rising, and the change of aglycones, biflavones and ginkgolic acids were clear while flavonoid glycosides were reobscure. Both increased with high solid liquid ratio, and the change of aglycones and ginkgolic acids were clear, while the change of flavonoid glycosides was obscure. The extracting rate decreased obviously and the amount increased unobviously when solid liquid ratio was higher than1:10. With extraction times increasing, the single extraction change rate of the four kinds of active components decreased rapidly, while the single extraction change rate of flavonoid glycosides was relatively small. The amount of the forth extraction of flavonoid glycosides, aglycones, biflavones and ginkgolic acids were 1.2 % 、1.1% 、2.5%、2.1 % of the first extraction.

(3) Using medical alcohol as the extraction agent, the best processing condition was confirmed by orthogonal experiment. The solid liquid ratio was 1:10 and extracted for 30min at 40℃~60℃ for 3 times. The order of flavonoid glycosides and total flavonoids influenced by different conditions was timegt;timesgt;temperaturegt; solid liquid ratio. The order of aglycones was timegt; temperaturegt; timesgt;solid liquid ratio. And for biflavones and ginkgolic acids, the order was timesgt;timegt;temperaturegt; solid liquid ratio.

Key Words：Ginkgo biloba ；Extraction conditions；Process optimization；orthogonal experiment

目 录

第1章 绪论 1

1.1 银杏简介 1

1.2.银杏的研究价值 1

1.3银杏黄酮和银杏酸的分子结构及其生理作用 3

1.3.1银杏黄酮 3

1.3.2 银杏酸 5

1.4.银杏外种皮中生物活性物质提取方法研究进展 7

1.4.1 黄酮类化合物提取 7

1.4.2银杏酸类化合物的提取 8

第2章 银杏外种皮中黄酮和酚酸提取工艺及溶剂选择 10

2.1实验方法 10

2.2银杏外种皮中黄酮和酚酸的含量检测 11

2.3银杏外种皮中黄酮和酚酸探索性试验 11

2.3.1提取方式和提取溶剂的选择 11

2.3.2单因素试验 14

2.4本章小结 18

第3章 银杏外种皮中黄酮和酚酸提取优化 19

3.1银杏酸的正交实验及其结果分析 20

3.2黄酮苷的正交实验及其结果分析 21

3.3黄酮苷元的正交实验及其结果分析 22

3.4双黄酮的正交实验及其结果分析 23

3.5总黄酮的正交实验及其结果分析 24

3.6本章小结 25

第4章 结论 26

第5章 致谢 27

参考文献 28

第1章 绪论

1.1 银杏简介

银杏是银杏科、银杏属落叶乔木。银杏树的果实俗称白果，因此银杏又名白果树。银杏树生长较慢，寿命极长，自然条件下从栽种到结银杏果要二十多年，四十年后才能大量结果，因此又有人把它称作“公孙树”，有“公种而孙得食”的含义，是树中的老寿星，具有观赏、经济、药用价值。

银杏出现在几亿年前，是第四纪冰川运动后遗留下来的裸子植物中最古老的孑遗植物，为原产我国的植物，雌雄异株^[1]。现存活在世的古银杏树稀少而分散，上百岁的老树已不多见，和它同纲的所有其他植物皆已灭绝，所以银杏又有活化石的美称^[2]。