Studies On The Comprehensive Extraction And Purification Processes Of Polysaccharides And Saponins In Astragalus

Industrial synthetic antioxidants and functional components which is used in the skin care fields expose more and more harmfulness, for these reasons there is a growing empHasis on the security issues of skin care products we daily contact with. Therefore, exploring the green safe natural functional additives has broad prospects. In this paper we took the Astragalus polysaccharides and saponins as target components, and to lay a foundation for its application in skin care products by exploring the comprehensive extraction and purification procedure of Astragalus saponins and polysaccharides.The influence factors of material liquid ratio, extraction temperature, extraction time and extraction times on the effect of ethanol extraction of saponins and water extraction of polysaccharides was researched by Single factor test and L9 (34) orthogonal experiment. Optimal comprehensive extraction technique of Astragalus polysaccharides and saponins was determined. The optimal extractive conditions obtained was:first treated with 75% alcohol extraction, ratio of solid to liquid 1:10, extracted at 70℃,2 h for 3 times, then dried herbs was extracted by distilled water, ratio of solid to liquid 1:6, extracted at 100℃,2 h for 2 times. The yields of polysaccharides and saponins was 0.119 g/ g pharmacognosy,6.624 mg/ g pharmacognosy.After exploring the effects of different factors on the purification, ethanol precipitation procedure was determined. Ethanol precipitation procedure:Astragalus polysaccharides solution was concentrated to 1 g pharmacognosy/mL, the time of ethanol precipitation was 3 h,2 times was nedded, ethanol was added to a concentration of 80%, impurities removal rate could reach 48.12% and retention rate was 82.29% on average.Papain was selected to remove the proteins in the Astragalus polysaccharides solution after contrast test, then the best craft was confirmed by using Single factor test and orthogonal experiment. The best parameters:pH value of the solution was adjusted to 5, the papain dosage was 5%, enzymed 3 h at a constant temperature of 50℃, the removal rate of proteins was 88.04% and loss rate of polysaccharides was 12.56%. Savage reagent was used once after enzymatic treatment, removal rate of proteins was 91.20%, higher than enzymatic treatment without Savage reagent, loss rate of polysaccharides was 14.45%.After comparing static adsorption and desorption properties, D101 resign was selected to purify Astragalus saponins. The best adsorption condition:Astragalus saponins solution was concentrated to 1 g pharmacognosy/mL, feeding rate 2 mL/min, feeding volume 45 mL.the best elution condition:first with 120 mL of distilled water to elute impurities, then with 100 mL of 70% ethanol to elute Astragalus saponins, the flow rate of eluent was 2 mL/min. The purity of Astragalus saponins purified was up to 84.59% and recovery was 87.52%.