Abstract: Taking extraction yield of polysaccharides as evaluation indexes,water-extraction and alcohol- precipitation method was applied for the extraction of polysaccharides from Phellinus linteus. Orthogonal experiment was used to investigate the effect of extraction temperature,extraction time and solid to liquid ratio on the extraction yield of the polysaccharides.The results showed that extraction temperature and solid-liquid ratio had a significant impact on the extraction yield of polysaccharides,but extraction time was not significant.The optimal extraction conditions were extracting at 80 ℃ for 2 h with solid to liquid ratio of 1:40 g/mL.Under the above conditions,the average extraction yield of polysaccharides was 3.20%.The highest polysaccharides yields was achieved by precipitation with 70% ethanol for 12 h.The results of antioxidant activity experiments in vitro displayed that the total antioxidant capacity,the hydroxyl radical and superoxide anion free radical scavenging activity increased with the increasing of polysaccharides concentration within the experimental range.

Key words: Phellinus linteus, polysaccharides;extraction;antioxidant activity