Effects of different drying methods on chemical properties and antioxidant activities of polysaccharides extracted from Epimedium

The study aimed to explore the effect of drying methods on the chemical properties and antioxidant activities of polysaccharides extracted from Epimedium,three polysaccharides( EAP- H,EAP- V,EAP- F) were obtained from Epimedium acuminatum Franch.via methods such as air drying,vacuum drying and vacuum freeze drying,respectively. Their neutral sugar,uronic acid and protein content were studied,and antioxidant activities were investigated on the basis of assay for DPPH radical,hydroxyl radical,superoxide anion free radical scavenging ability. Results showed that Epimedium polysaccharides were acidic polysaccharides containing a small amount of protein,different drying methods could affect their monosaccharide composition and uronic acid content; compared with air drying and vacuum drying methods,vacuum freeze drying method resulted to Epimedium polysaccharides with higher uronic acid content,stronger antioxidant abilities of DPPH radical,hydroxyl radical and superoxide anion free radical scavenging ability. As a result,vacuum freeze drying method was the best choice for the preparation of the Epimedium polysaccharides.