【作者】 陈益乐；

【导师】 段更利；

【作者基本信息】 复旦大学 ， 药物分析学， 2011， 硕士

【摘要】 传统的中药活性成分提取方法存在溶剂消耗量大、费时、操作步骤繁琐或活性成分提取率不高、杂质清除率低等问题,是导致现有中成药质量难以控制、疗效难以稳定的重要原因之一,也严重阻碍了中药现代化的进程。因此,研究、开发和采用新的中药提取及制药新工艺、新技术是目前研究工作者亟待解决的课题。红外辐射是介于可见光与微波之间的电磁波,物质的分子在吸收红外能后,可使光子的能量转变成分子的振动或转动能量。可以设想,在红外辐射下,基质内部温度可迅速上升,并增大被分离物质在介质中的溶解度；同时红外辐射还可加速被萃取成分向溶剂的扩散,从而缩短提取时间,提高提取效率。本研究基于以上设想,采用市售的普通硬质红外灯泡作为辐射光源,以丹参、大青叶等常用中药材作为研究对象,对红外辅助提取酚酸类、二萜醌类、生物碱类及挥发油类等典型的中药有效成分的可行性进行了考察。在第一章中,我们建立了红外辅助提取法与高效液相色谱法连用,同时提取分析了丹参中4种水溶性的酚酸类有效成分和4种脂溶性的二萜醌类有效成分,并将该法与常用的几种提取方法进行了比较。经正交实验优化后的红外辅助提取的条件为：提取时间：15min,提取溶剂：70%的甲醇水溶液,固液比为0.1：15(g/mL)。在优化后得到的色谱条件下,8种待测组分在所考察的浓度范围中线性良好(r>0.9994),天间精密度和天内精密度均达到要求,回收率在96.90%104.30%之间,RSD均小于2.5%。最后,我们对不同产地的多批丹参药材中的活性成分进行了提取分析。通过使用红外辅助提取技术,能在较短的时间内从丹参中提取出8种有效成分,其提取出的量与传统提取技术,例如水浴回流提取,超声提取法以及微波辅助提取相比大致相当,有些更高。在第二章中,我们对红外辅助提取法在吲哚生物碱类有效成分中的提取应用作了研究,选取的代表性中药材为大青叶。同时,为了进一步考察红外辅助提取法相对传统提取方法的优势或劣势,我们同样将红外辅助提取法与索氏提取法、超声辅助提取法和微波辅助提取法进行了比较。在这一章中,我们在对提取溶剂、提取时间、固液比等影响因素进行优化之外,还考察了红外光源的功率对提取结果的影响。经实验得到的最佳提取条件为：提取溶剂为三氯甲烷,红外灯功率为275W,提取时间为20min,固／液比为0.1：20(g/mL)。在优化的色谱条件下,靛蓝与靛玉红在所考察的浓度范围中线性良好(r>0.9996),天间精密度和天内精密度均达到要求,回收率大于96.0%,RSD均小于2.0%。虽然红外辅助提取法所用的提取时间较微波辅助提取法较长,但与索氏提取法和超声辅助提取法相比,其提取时间还是大大缩短了。对于靛蓝来说：通过这四种提取方法得到的提取量按多少排序,分别为：红外辅助提取法>微波辅助提取法>索氏提取法>超声辅助提取法；对于靛玉红,这四种提取方法得到的提取量按多少排序分别为：索氏提取法>红外辅助提取法>微波辅助提取法>超声辅助提取法。为进一步对红外辅助提取法适用的提取物质类型进行研究,在第三章中,我们选择孜然中的挥发油成分作为提取目标,考察了红外辅助提取技术在中药挥发油成分提取方面的可行性,同时辅以氮气吹扫无溶剂固相微萃取的手段,开创了一种新的挥发油提取方法。我们对固相微萃取头的类型及提取时间等主要的影响因素进行了简单的优化,得到最佳的提取条件为：采用75μm CAR/PDMS涂层的固相微萃取头,红外光源的功率为275W,提取时间为2min。在优化后的气相色谱和质谱条件下,通过GC-MS分离鉴定得到的孜然挥发性化合物共有28种,与文献报道的较为相符。在前三章中,我们应用红外辐射对代表性中药中的几类不同的有效成分进行了提取分析,证明红外射线与微波辐射相似,对中药材中的活性成分具有同微波相当的提取效率,提取时间较短,成本低等优点。又由于采用微波辅助合成反应被广为报道,因此,我们在第四章中对红外辐射是否可以同微波一样应用到有机合成反应中作一个简单的初步型探究。水杨酸甲酯的合成实验是有机化学教学中的经典实验,故我们选用该合成实验来考察红外射线用于有机合成的可行性。结果证明红外辐射用于简单有机合成反应是可行的。该方法同传统的水浴回流和微波辅助反应一样,亦是通过红外射线对反应原料的致热效应来实现的。但是由于红外光源的功率较微波低,红外辐射辅助反应相对微波辅助反应来说致热效应也相应的低,但较水浴回流来说要强。所以导致微波辅助反应所需的时间最短,红外辅助反应次之,水浴回流最长。本研究的研究结果将有望为中药活性成分提取的工艺改进提供一种新的思路,为中药现代化的推进奠定必要的技术基础,对中药的提取分离精制及天然保健品的制备和生产具有重要的应用价值和广阔的应用前景。更多还原

【Abstract】 It is well known that conventional extraction techniques, including solvent extraction, Soxhlet extraction, heat-reflux extraction, et al., often involves large solvent consuming, long extraction time, low extraction rate or low percentage impurity clearance. It was also reported that microwave-assisted extraction and supercritical fluid extraction had been employed to extract the active compounds from TCMs. But these methods both need sophisticated equipments (microwave oven or supercritical fluid extraction system) and high cost. Therefore, developing a simple and low-cost extraction method is still in great needs nowadays.As an important form of electromagnetic wave, infrared radiation (IR) has wavelengths between about 750 nm and 1 mm. IR has been widely employed as heat resource for health care due to its high penetration ability. Infrared can also be used in cooking and heating food as it predominantly heats the opaque, absorbent objects, rather than the air around them. The high efficiency of the infrared heater is achieved by matching the wavelength of the infrared heater to the absorption characteristics of the material.In this study, we focused on developing a new extraction method for separation and determination of active compounds in TCMs (Traditional Chinese Medicine) using the commercial infrared bulb as infrared radiation source. The infrared-assisted extraction of combined with modern chromatographic methods, were applied for separation and qualition of different kinds of target compounds such as phenolic acids, diterpenoids, alkaloids and volatile oils from TCMs.In chapter 1, an infrared-assisted extraction (IRAE) method was developed and coupled with high-performance liquid chromatography (HPLC) for simultaneous determination of four phenolic acids and four diterphenoids in radix Salviae Miltiorrhizae (Chinese name Danshen). The extraction conditions of IRAE were optimized using orthogonal design, and the optimal conditions were as follows: extraction time of 15 min; extraction solvent of 70%(v/v) methanol in water solution, and solid/liquid ratio of 0.1:15 (g/mL). Under the optimized chromatographic conditions, all the target compounds were well separated with high resolution. Good linearity (r>0.9994) was observed over the concentration ranges investigated, and intra-day and inter-day precision were high. Recoveries of the eight compounds were from 96.90%-104.30% and relative standard deviations (RSD) were below 2.5%. By using this IRAE method, with a much shorter extraction time, the determined amounts of the eight active components of Danshen were comparable with or even higher than those extracted with conventional heat-reflux extraction and ultrasound-assisted extraction methods. The IRAE method was further established by simultaneous quantification of the four phenolic acids and four diterpenoids in Danshen from different geographic origins.In chapter 2, the developed IRAE-HPLC method, was employed to determination of indigo and indirubin in leaves of Isatis indigotica Fort. (Chinese name Daqingye). This newly developed and optimized infrared-assisted extraction (IRAE) method was compared with ultrasound assisted extraction (UAE), Soxhelt extraction (SE) and microwave-assisted extraction (MAE) in terms of extraction amounts of these two active components. Besides the influence factors mentioned in chapter 1, we also investigated the effect of different infrared power on the extraction results. The optimal conditions were as follows:extraction reagent of trichloromethane; power of infrared lamp of 275W; extraction time of 20 min; liquid/solid ratio 20 mL/0.1g. Under the optimized chromatographic conditions, indigo and indirubin were well separated with high resolution. Good linearity (r>0.9996) was observed over the concentration ranges investigated, and intra-day and inter-day precision were high. Recoveries of these two compounds were above 96.0% and relative standard deviations (RSD) were below 2.0%. The results showed that the amounts of indigo extracted by IRAE were a little higher than that extracted by other three extraction methods, while for indirubin, the amount obtained by MAE reached the highest.In chapter 3, we employed, for the first time, a novel strategy for extracting essential oil compounds from cumin with nitrogen purge-solvent free-infrared assisted-solid phase microextraction (IRAE-SPME) coupled with gas chromatography mass spectrometry (GC-MS). Some parameters, including SPME fiber coating and irradiation time, were optimized. The optimal conditions were as follows:SPME fiber coating of 75μm CAR/PDMS; power of infrared lamp of 275W; irradiation time of 2 min.28 volatile substances was obtained by GC-MS and the results showed the method is simple, rapid and solvent-free.Since the use of microwave radiation for organic synthesis has been widely reported, we were interested in that whether the infrared radiation could be applied to the organic synthesis. So, in chapter 4, a simple method for synthesis of methyl salicylate using infrared radiation has been developed. The results showed that using infrared radiation for simple organic reactions is practicable.In summary, the main contributes of this dissertation is that we initially investigated the feasibility of extraction active components from TCMs with infrared radiation. The developed methods were successfully applied to separation and analysis of phenolic acids, diterpenoids, alkaloids and volatile oils from different plant materials. We also established a method to synthesis of methyl salicylate using new infrared radiation. We aimed at exploring and finding out new techniques in sample preparation of plant material analysis, so that more breakthroughs can be obtained in the quality control research study of TCMs.更多还原