Extraction process of polysaccharide by compound enzymatic method of Dendrobium officinale and its antioxidant activity

In this paper,the suitable enzymatic extraction method and the antioxidant activity of Dendrobium officinale polysaccharides(DOP)were studied. The effects of enzymatic ratio,enzyme concentration,temperature,extraction time,solid-liquid ratio and pH on yield of polysaccharides were investigated,on the basis of single-factor experiments and orthogonal test for enzymatic action. The optimized extraction conditions were:Dispase and Cellulase ratio of 2:1,enzyme concentration of 10%,solid-liquid ratio of 1:120,extraction temperature of 55℃,pH6.0,extraction time of 3 h,the yield of polysaccharides were 43.85%±1.8%,antioxidation results showed that the DOP extracted by enzymatic method had an obvious antioxidant activity,the IC₅₀ values of DPPH and ABTS free radical scavenging abilities were 1.331,0.467 mg/mL,Dendrobium officinale polysaccharides had good antioxidant activity.