Abstract:In order to understand the changes of polysaccharide content in Gentiana apiata before and after flowering, the extraction process of polysaccharides was optimized by response surface method, and the antioxidant activities of polysaccharides were determined. The results showed that the content of polysaccharide in G. apiata after flowering was higher than that before flowering. The optimal extraction process were extraction 3 h, the solid-liquid ratio of 1∶16, the alcohol precipitation ratio of 1∶10, and the centrifugal speed at 1 537×g. Under optimal extraction conditions, the extraction rate of polysaccharide was 5.13%, close to the predicted value of 5.42%. Polysaccharides had certain antioxidant capacity to DPPH and ABTS, which was higher than that of Vitamin C and butylated hydroxytoluene. Therefore, it was suggested that G. apiatacan also could be used as antioxidant in food and health care products except for medicine.