Preparation, Structural Features And Radioprotective Effect Of Polysaccharides From Angelica Sinensis (Oliv.) Diels

Radix Angelica sinesis is a well-known oriental herb belonging to family Umbelliferae. Because of its broad pharmacological effects, it has been used for thousands of years in traditional Chinese medicinal prescriptions. Polysaccharide fraction from A. sinesis is the primary component which exhibits a variety of biological activities. Until now, studies about polysaccharide of A. sinesis in China are emphasized particularly on its biological activities, such as immunostimulating and antitumor activity, but few in-depth study on its chemical properties. The objective of this dissertation is to study the methods of preparation, structural features and radioprotective effect of polysaccharide from A. sinesis. The main results of research are as follow:The chemical composition of powder of Angelic sinesis were analyzed: 11.0% of moisture, 18.5% of protein, 3.8% of crude fat, 8.1% of ash, 9.6% of crude fiber, 37.7% of reductive sugar, and 10.1% of polysaccharide. The yields and extraction rates were compared between the water-soluble crude polysaccharide W-ASP and the EDTA/alkali-soluble crude polysaccharide E-ASP: W-ASP yields 10.8%, accounting for 71.1% of the total yield (15.2%); E-ASP yields 4.4%, accounting for 28.9% of the total yield (15.2%), which indicated that W-ASP is the main constitutes. The extraction rate of W-ASP was 5.7%, with 56.4% of total polysaccharide content (10.1%); The extraction rate of E-ASP was 1.8%, with 17.8% of total polysaccharide content. The chemical components of W-ASP and E-ASP were: 54.36%/43.82% of polysaccharide,24.80%/36.26% of uronic acid, 8.34%/14.40% of protein, 21.66%/19.73% of ash, respectively. Neutral sugars were mainly composed of galactose, arabinose, glucose, rhamnose and short part of mannose. The content of uronic acids, protein, and glucose of E-ASP are all higher than that of W-ASP.Peripheral leucocyte and lymphocyte counts, as well as weight were chosen as screening targets for radioprotective effect. The results showed that W-ASP and E-ASP could protect peripheral leucocytes and lymphocytes of mice against radiation induced damage, and accelerate the weight simultaneity, but the effect of W-ASP was better than that of E-ASP. The technology parameters for extraction of water-soluble polysaccharide W-ASP from A. sinesis were optimized by response surface analysis (RSA): extracting for 2 h at 85°C, with 1:10 ratio of A. sinesis powder to water and with 2 times'repetition.Fractionation and chemical composition of water-soluble crude polysaccharide from A.