Optimization of enzymatic extraction of polysaccharides from Sterculia lychnophora by central composite design

Conditions of extracting Sterculia lychnophora polysaccharides were optimized by central composite design and response surface methodology. The effect of cellulase concentration, liquid/solid ratio, extraction time and temperature on the yield of polysaccharide were investigated by single factor experiments. Subsequently, the center combination experimental design was used to investigate the effect of former three factors on the yield of polysaccharides extraction. The optimum combination was obtained by design expert 8 . 06 and response surface analysis . The effect order of 3 factors on yield was as follows : cellulase concentration>extraction time>liquid/solid ratio. The optimum extraction conditions were cellulase concentration 1.92% , liquid/solid ratio 1∶30.5, pH4.8 and 50℃ for 126min. Under this condition, the optimum polysaccharide yield of Sterculia lychnophora was 7.92%±0.09%.