Abstract: Objective: To optimize the ultrasound-assisted extraction of polysaccharides from okra by response surface analysis. Methods: On the basis of single-factor experiments, the relationship between the yield of polysaccharides and main extraction conditions including extraction time, liquid/solid ratio and temperature was modeled using a 3-factor, 3-level Box-Behnken experimental design and further, the established model was analyzed by response surface methodology to obtain the optimum extraction conditions. Results: The optimum extraction conditions were obtained as follows: extraction time of 20 min, liquid/solid ratio of 44:1 and temperature of 52 ℃. Under these conditions, the estimated and observed values of maximal yield of polysaccharides were 27.82% and 27.75%, respectively. Conclusion: The results provide a reference for extraction of okra polysaccharides, and lay a foundation for future research on okra.

Key words: okra, polysaccharides, ultrasound-assisted extraction technology, response surface methodology