药材活性成分在亚临界水/二氧化碳混合流体中的溶解热力学和动力学研究

Cardiovascular disease is a common disease in our country. Medicinal herbs have been generally used in healthcare system in China for thousands of years and recently have attracted increasing interest. The main extraction methods include the decoction in aqueous solution and heating in volatile organic solvents. These methods need long extraction time, use the volatile solvents and cause the environmental pollution. It is urgent to develop an efficient, green, and controlled new extraction method. Subcritical water and carbon dioxide and are the commonly used green solvents. Researchers mainly focus on optimizing the process conditions; however, the study on the extraction mechanism is sparsely. The extraction of active ingredients from herbs is a key step of the modernization of traditional Chinese medicine. Study on controlled-extraction of active ingredients from genuine regional drugs by green solvents is an important issue. This study will focus on the extraction of active ingredients from three test materials. Herein, compressed carbon dioxide is introduced into the system. This project will focus on the mechanism of mass transfer on the extraction of three kinds of typical herbs by compressed carbon dioxide/water technology. The extracts will be qualitatively and quantitatively analyzed by infrared spectroscopy (IR), nuclear magnetic resonance (NMR), UV/vis spectrophotometer and other spectroscopy methods. Through changing external factors (the ratio, temperature, pressure, and particle sizes) in the extraction system, it will reveal the physicochemical properties of the system, and summarize the extraction rules of different ingredients and the corresponding relationship between properties of mixed solvent and extraction rate. This study involves the Chinese material medica, chemical thermodynamics, chemical kinetics, supercritical fluid science and technology. Therefore, this study can not only promote the development of related sciences, but also expand the application of supercritical fluids.

心血管病是我国的常见病，道地药材丹参、瓜蒌子、灯盏细辛对治疗该病有独特的优势。目前这三种药材活性成分的提取主要采用溶剂法，常用甲醇、二氯甲烷、三氯甲烷等，这些溶剂易挥发，提取时间长，造成有机溶剂残留。因此，当前需要发展一种无毒、高效的新型提取方法。.亚临界水和二氧化碳是常用的绿色溶剂，具有无毒无害等优点，目前关于亚临界水和二氧化碳混合流体提取中药治疗心血管病的药效成分的研究很少。本项目拟研究亚临界水、二氧化碳混合流体提取三种道地药材的药效成分。通过研究不同温度下药效成分的溶解度和稳定性，得出药效成分溶解过程的热力学参数和溶解规律；采用紫外、核磁共振等技术，优化混合流体比、时间、温度等参数，通过对二氧化碳、水和药材分子间相互作用的分析，系统研究体系的宏观动力学性质，建立动力学模型。本项目旨在促进中药治疗心血管疾病药效成分的发展，体现了中药学与绿色化学的学科交叉。

本研究工作基本按计划执行。研究了三种道地药材丹参、瓜蒌子、灯盏细辛的亚临界水提取方法，优化了最佳提取条件，研究了二氧化碳对提取产量的影响。完成以下研究内容： .（1）丹酚酸B在130-210 ℃范围内主要的降解产物有原儿茶醛、丹参素、丹酚酸F、丹酚酸E、丹酚酸A和丹酚酸C等。由丹酚酸B降解为丹酚酸A，丹酚酸A转化为丹酚酸C，最后生成丹参素等化合物为主要反应途径。建立了在亚临界水中丹酚酸B主要降解路径的动力学模型。通过模型可知丹酚酸B在170 ℃左右转化为丹酚酸A的得率较高，温度在150 ℃左右有利于得到丹酚酸C。温度在130-180 ℃范围内温度越高则丹参素的得率越高。 .（2）亚临界水体系下，瓜蒌子的最佳提取条件为：提取温度130 ℃，提取时间10 min，料液比1:33，3,29-二苯甲酰基栝楼仁三醇提取率是0.102%，多糖提取率高达5.57%。.（3）亚临界水体系下，灯盏细辛的最佳提取条件为：提取温度130 ℃，提取时间5 min，料液比1:25，药材颗粒度70～100目，灯盏花总黄酮的提取率是10.72%。亚临界水提取技术所得到的灯盏花中总异黄酮的提取率明显要比采用甲醇、乙醇回流提取法及超声提取法得到的提取率高。