Study Of Supercritical Fluid Extraction And Analytical Method Of Active Components From Epimedium

The active components of Epimedium are research focus in Chinese traditional medicine. Modern pharmacology research shows that Epimedium has a variety of medical functions, mainly affects immune system, reproductive system, cardiovascular system and has anti-aging effect. It has high value for remedy and healthcare. The chemical components of Epimedium are mainly flavonoids, alkaloids, polysaccharides. Icariin is one of the major active components of Epimedium.The separating methods of active components from Epimedium appeared a lot in documents. Among them, the organic solvent extraction is used widely. All these methods have shortcomings, such as the product cannot avoid organic solvent remainder due to using a large amount of organic solvent, time-consuming and not suitable for thermal instable materials. Supercritical fluid extraction (SFE) is friendly to environment. It can reduce organic solvent residual. As a new technology it has broad prospects.The aim of this experiment was to use SFE extract active components from Epimedium, optimize the extraction conditions and prepare for new drugs production.The main contents are as follows:(1) The analytical methods including high performance liquid chromatography and thin-layer chromatography were established to detect flavonoids and alkaloids in Epimedium. Acid-base titration was adopted to detect total alkaloids in Epimedium. A new method for preparing sample solution was established. Many kinds of samples with different active components could be prepared from one scheme. It could reduce operation time.(2) Single factor experiment and central composite design-response surface method were used to optimize SFE for extracting active components from Epimedium. Independent variables were extraction temperature, extraction pressure and entrainer flow rate. Dependent variable was extraction rate of icariin. A two-order polynomial equation was fitted to the data. From the response surface graph and two-dimensional contour plot, the optimized extraction conditions could be concluded as follows: extraction temperature 46.5℃, extraction pressure 30.6 MPa, entrainer flow rate 3.3 mL/min. The suitability of the model equation for predicting the optimized response values was tested using the recommended optimized conditions. The experimental values were found to be in agreement with the predicted ones.(3) SFE method was compared with organic solvent extraction. The advantages and disadvantages were summarized. The results can offer guidance for the further utilization of SFE technology.