Study On The Separation And Enrichment Of The Active Constituents In Chinese Herbal Medicine By Flotation

With the Progress of modemization of Chinese traditional medieine,the separation and enrichment method the active components of Chinese herbal medicine is becoming an indispensable part. In recent years, with the significant progress of separation, a number of effective separation methods of separation of Chinese herbal medicine such as supercritical fluid extraction technology, semi-bionic extraction, ultrasonic extraction, large macroporous resin extraction technology and high-performance liquid chromatograpy, droplet counter-current chromatography has been established at home and abroad besides the classic method. This paper cited a new type of separation - flotation separation technology in the separation of the active ingredients of Chinese herbal medicine enrichment.Flotation separation is a kind of separation technology which is based on the different adsorption property at the bubble surface for the materials. The necessary condition for foam separation is that the solution must contain surface active ingredients, whereas herbal active ingredients (such as: saponins, proteins, gums and other polymers) has surfactant properties. Accordingly, the stabile bubble can come into being when the solution is strongly stirred or boiling. There are two commonly used methods for the flotation separation which are solvent and foam flotation. The choice of separation method is based on the physical and chemical properties of the product while the entire separation system will also determine the flotation effect.In this investigation, the flotation separation was used to separation and preconcentration the active ingredients in rhubarb and notoginseng. We investigate the effects of several factors such as flotation solvent, nitrogen flow rate, test solution pH, flotation time and the electrolyte and obtain the optimum flotation conditions as follows: (1) solvent flotation of aloe-emodin, emodin, chrysophanol, and physcion in rhubarb: sublation solvent was n-pentanol, the concentrition of feed was 6.4mg/mL, floatation time was 30min, pH=1~2, the flow rate of nitrogen gas was 20 mL/min, the concentration of NaCl was 0.4mol/L.(2) foam flotation of Rg1,Re,Rb1 and Rd in notoginseng: the concentrition of feed was 2.0mg/mL, pH=2~3, the rate of nitrogen gas was 20mL/min, floatation time was 10 min, the concentration of NaCl was 0.2mol/L.The product separated and concentrated under the optimal conditions was detemrined by high performance liquid chromatography.Comparing with other separated methods , solvent sublation technique is possessed of such excellence:rapid separation,simple operated technology and low cost. still needs a further investigation.