Abstract: In the present study,the conditions for ultrasonic-assisted extraction of polysaccharides from Fructus Mori were optimized by response surface analysis.On the basis of single-factor experiments,the relationship between main extraction conditions including extraction time,the ratio of water to raw material and extraction temperature were modeled using a 3-factor,3-level Box-Behnken experimental design.The established model was analyzed by response surface methodology to obtain the optimum extraction conditions.The results showed that the optimum extraction conditions were obtained as follows:extraction time was 23.5 min,the ratio of water to raw material was 27:1 (v:m,mL/g) and extraction temperature was 72 ℃.Under these conditions,the estimated and observed values of maximal extraction yield of polysaccharides were 17.80% and 17.78 ± 0.85%（n=3）,respectively.The method had the advantage of time-saving and efficient compared with the traditional water extraction.The results reported in this study provided the experimental basis for the follow-up research and development of Fructus Mori polysaccharides.

Key words: Fructus Mori, polysaccharides, ultrasonic-assisted extraction technology, response surface methodology