Abstract: Dendrobium officinale is a kind of traditional Chinese medicine.It contains a variety of active ingredients,such as alkaloids and polysaccharides.In this study,the flash extraction technology and enzymatic hydrolysis were used to extract alkaloid,joined and free polysaccharide from D.officinale.The enzymatic hydrolysis conditions were optimized using a series of one-factor-at-a-time experiments.The results showed that the optimal extraction conditions were as follows:1:30 material/solvent ratio,32 U/g cellulose,39200 U/g papain and 2.5 h hydrolysis time.The extraction yields of alkaloid,joined and free polysaccharide were:0.136%,4.2% and 19.3%,respectively.The purities were:78.2%,81.3% and 90.6%.The molecular weights of joint and free polysaccharides were 2373 Da and 17987 Da,which were determined by GPC.This study developed a combined extraction process of alkaloids and polysaccharides from D.officinale.The process was efficient,convenient and suitable for industrial production.

Key words: Dendrobium officinale, combined extraction, alkaloids, polysaccharides