Studies On In Vitro Propagation And Inhibiting Tumor Of Dendrodium Candidum

Dendrobium candidum is one of the well known traditional Chinese medicines,with higher medicinal and economic value.It has been accepted by the "Chinese Pharmacopoeia"(2005 edition).In natural condition,it is different to grow due to the seed is very small,in addition, in recent years the excessive gather and the destruction of natural habitats,D.candidum wildlife resources increasingly decreaseing.Therefore,rapid propagation has been studied using the biotechnological method in this study,for replacing and protecting D.candidum in nature.Suitable culture condition of proliferation and rooting for D.candidum using the node of D. candidum as sterile culture was screened.The results show that the survival rate of implant reaches 85%and sterile rate is 90%,after sodium hypochlorite disinfect for 8 min.MS medium is the best medium for the growth of D.candidum.The heavy of D.candidum proliferat in 60 d.Dendrobium candidumthe proliferation of high multiples of 3.2 times when use NAA 0.4 mg·L^-1and 6-BA 5 mg·L^-1to subculture.D.candidum take root,the rate reached 96.67%when NAA 0.3 mg·L^-1and 6-BA 2 mg·L^-1in medium.The present study also include the influence of natural additives to D.candidum.The bananas juice can promote plant growth,root stout,tidy,stem diameter section short.It could significantly promote the proliferation D.candidum the bud,reaching 4.98 times.Banana juice also can contribute to the accumulation of alkaloids and polysaccharides(2.8 mg·g^-1and 19.2%,respectively).The multiples of the weight gain to 3.51 times when added 20%potato juice.The role may relate to natural additives in plant hormones and related soluble sugar. Potatoes contain a wealth of growth hormone and cytokinin(1.07μg·g^-1and 0.89μg·g^-1, respectively),and the content of ABA in bananas has reached 4.61μg·g^-1.Both potatoes and bananas are rich in soluble sugar.A total of 11 mycorrhiza were isolated from the Phalaenopsis and Dendrobium,the fermented liquid,extracts of mycelium and broth and broth mixture of mycelium of them were used to study.The results showed that the strain ph5 is the most conducive to weight gain and D.candidum dry matter and the role of the fermented liquid extract of the mycelium is the strongest.At the same time,hormone and cytokinin synthesis were promoted.ABA content was significantly higher than the normal control group.D.candidum in vitro and in vivo has significant anti-tumor activity.Mice experiments show that D.candidum S180 can significantly prolong survival in mice ascites,inhibit tumor growth and increase the proportion of immune organs,raising the number of peripheral white blood cells,has significant anti-tumor activity.