Research On The Extraction Process Of Saponins And Polysaccharides From Radix Astragalus

Radix Astragalus, which is commonly used in traditional Chinese medicine, has manyeffects, such as depressing blood pressure, replenishing “qi”, diminishing inflammation,stimulating hearts, reinforcing immunity, promoting the subsidence of swelling, and so on.Radix Astragalus is the rhizome of Astragalus Membranacens Bunge and Astragalusmenbranacens var. mongolicus (Bunge) Hsiao. The main effective compositions areAstragalus saponins and Astragalus polysaccharides.In order to extract saponin and polysac-charides efficiently from Radix Astragalus, inthe present study, we want to optimize extracting possess, which is superior to thetraditional extraction methods, as well as to develop method for the determination ofsaponin and polysac-charides from Radix Astragalus. As a result, the quantity of saponinextracted by non-water alcohol is satisfactory after impurities are eliminated. The quantityof polysaccharides extracted in this method is more than that in traditional methods. Thefrozen-dried polysac-charide has good character, water-solubility. So we infer that adoptingthe method designed in this technology to extract saponin and polysaccharides in radixastragalus can get better purity and quantity than those in traditional methods and it isoptimal for the utilization of radix astragalus. The ethanol-alkali solvent was used toextract the saponin in radix astragalus. The optimum extraction condition is identified bythe uniform design experiments. The extraction rate of saponin extracted by theethanol-alkali solvent which reached2.638%was1.08times as much as that extracted by95%ethanol, which is reported to be the best, and1.54times as much as that by70%ethanol in soxhlet which is an often used method.This paper studied on extraction methods of valid componpents astragalus as index tostudy the effects of five extraction factors by single factor investigation, the ratio ofmaterial to extraction solvent, extraction temperature, extraction time and ethanolconcentration of extraction solvents. The extraction rate of astragalus method was detectedby ultraviolet spectrophotometry and infrared spectrometry. The results exhibited that thebest extraction solvent is1:10, the best extraction temperature is90C, and the bestextraction time is1.5hours. In this method the extraction rate of ethanol-alkali extractionmethod is better than the other methods.So, we can obtain the following conclusion that it apply this experiment’s method canget higher extraction rate than traditional ways for extracting the valid components in theChinese tradition medicine such as asponin and polysaccharide. It will be useful in veryvariety of applications for extraction of the efficiency components.