Studies On Separation And Extraction Of Alkaloids From The Chinese Medicinal Herbs With Strip Dispersion Hybrid Liquid Membrane

Alkaloid is a kind of bio-active compound existed in Chinese medicinal herbs. The separation and extraction of alkaloids are significant. Liquid membrane, as a simple, quick, effective, high-selective and economic separation and extraction technique, has been widely used in the fields of biological engineering, hydrometallurgy, extraction and separation metal ions and organic pollutant from the industrial wastewaters. However, the reports about separation and extraction of active ingredients from Chinese medicinal herbs using liquid membrane are very few due to the complex composition and multiinterferent of the herbs. For overcoming the shortages of the supported liquid membrane and the emulsion liquid membrane, a strip dispersion hybrid liquid membrane (SDHLM) is developed to separate and extract alkaloids in Chinese medicinal herbs. According to the need for transport larger molecule diameter of alkaloids, a kind of novel microporous polypropylene membrane with controlled pore sizes has been prepared via thermally induced phase separation. And the membranes employed as the supported membrane in SDHLM system to extract and separate alkaloids from Coptis was investigated. The details are as follows:1. This paper reviews the development history, the classification, the separation mechanism, and the applications of the liquid membrane technology. The characteristic and application of the SDHLM were elaborated in detail in this work.2. The separation and extraction of isoquinoline alkaloids, protopine, allocryptopine, sanguinarine, chelerythrine in the fruits of Macleaya cordata (willd) R. Br. were carried out with SDHLM system of D2EHPA-kerosene-HCl. Under the optimized experimental conditions, the permeability coefficients of protopine, allocryptopine, sanguinarine, and chelerythrine are reached 1.66,1.99,2.98, and 3.06×10-4 cm/s, respectively. And the transport efficiencies are 68%,77%, 83%, and 85%, respectively. The results indicate that the present SDHLM system can effectively extract and separate above four kinds of alkaloids from Macleaya cordata (willd) R. Br.3. A systematic research on the separation and extraction of isoquinoline alkaloids, jatrorrhizine, palmatine, and berberine from the Coptis roots with SDHLM system of D2EHPA-kerosene-H2SO4 was studied. Under the optimized experimental conditions, the permeability coefficients of jatrorrhizine, palmatine, and berberine are reached 4.43, 6.09,6.25×10-4 cm/s, respectively. And the transport efficiencies are 90.4%,92.1%,95.3%, respectively. The results show the three main alkaloids in Coptis roots can be separated and extracted effectively with the present SDHLM system.4. SDHLM system of D2EHPA-kerosene-HCl was developed for the separation and extraction of tetrahydropalmatine, palmatine, and dehydrocorydaline from the tuber of Corydalis yanhusuo W. T. Wang. Under the optimized experimental condition, the permeability coefficients of tetrahydropalmatine, palmatine, and dehydrocorydaline are reached 3.78,4.91, and 4.93×10-4 cm/s, respectively. And the transport efficiencies are 87.8%,94.2%, and 95.7%, respectively. The results indicate that the present SDHLM system can extract and separate the main alkaloids from Corydalis yanhusuo W. T. Wang effectively.5. Polypropylene microporous membrane with controlled pore sizes was prepared via thermally induced phase separation, using xylene as diluent and polyethylene glycol as the pore-forming agent. Scanning electron microscope and contact angle measurement were employed to charaterization of the surface morphology and the hydrophobic property of the membrane. The application of the prepared polypropylene microporous membrane in separation and extraction of alkaloids in Coptis was investigated with SDHLM. The results indicated that the prepared microporous polypropylene membrane is high performance.