Abstract:Eight kinds of macroporous resins were screened by adsorption efficiency，desorption efficiency，decolorization efficiency，and deproteinization efficiency of static adsorption，as well as desorption test with extraction of polysaccharides from Anoectochilus roxburghii.Using the adsorption and desorption results as indicators，the optimum macroporous resin was selected to investigate the technological parameters of purified polysaccharides.With vitamin C（VC）as the reference substance，the antioxidant ability of polysaccharides from Anoectochilus roxburghii before and after being purified was evaluated by determining the scavenging capacity of 1，1-dipheny1-2-picryl-hydrazyl hydrazine free radical（DPPH·）and hydroxyl free radical（·OH）.Results showed that the optimum macroporous resin was X-5.By a single factor test，the optimal sample loading and elution conditions were as follows：4 mg/mL of polysaccharides were loaded on the resin column with a volume of 4 BV at a flow rate of 2 BV/h and eluted with 5 BV of 40% ethanol at a flow rate of 2 BV/h.Under optimum conditions，the total polysaccharide content in Anoectochilus roxburghii increased from 27.88% to 76.07%，and the color of polysaccharides changed from brunette to light.The purified polysaccharides had a strong scavenging effect on DPPH·and·OH；when the polysaccharide concentration was 0.6 mg/mL，the clearance rate of DPPH·and hydroxyl radicals increased from 57.27% to 86.24% and 60.12% to 88.63%，respectively.Although it was lower than the scavenging effect of VC，the purified polysaccharides had an acceptable antioxidant ability，providing a reference for the industrial production and further development of polysaccharides from Anoectochilus roxburghii.