Optimization of Enzymatic Extraction Technology for Polysaccharides from Desmodium Styracifolium by Response Surface Method

OBJECTIVE To study the optimal technological conditions for extracting Desmodium styracifolium polysaccharides. METHODS According to Box-Behnken design principle and results of single-factor experiments, the quadratic polynomial mathematical model, response surface and contour line map were analyzed. The effects of enzymatic hydrolysis time, temperature and enzyme amount on the polysaccharides yield were explored by using yield and content of polysaccharides as evaluating indicators. RESULTS The degree of fitting and confidence level for mathematical model was satisfactory. Optimum extraction technology conditions were as follows: the ratio of liquid to solid 1∶40, pH 5.5, enzymatic hydrolysis temperature 49.94 ℃, time of 1.53 h and cellulase amount of 2.00%. The effect order of three factors on polysaccharides yield was as follows: enzymatic hydrolysis time>enzymatic hydrolysis temperature>enzyme amount. The interaction effects of different factors were highly significant. CONCLUSION Optimized extraction technology is stable, feasible, highly efficient. It could provide references for the industrial production.