Tin Caulis Dendrobii Tube Seedlings Regeneration System And Antitumor Activity

As one kind of Orchidaceae, Dendrobium is a perennial epiphytic herb, also known as Dendrobium candidum. The helical body, formed by the Dendrobium officinale which has been dried, is called Dendrobium. Distributed in provinces in south and southwest, Dendrobium is attached on the wet trunk of trees or in the crack of stones, accompanied by some kind of plant such as moss. Due to the very low germination of seeds of Dendrobium under natural conditions, the wild Dendrobium has been endangered. With the constantly breakthroughs of the tissue culture and planting techniques during these years, planted by human being has been an important approach instead of wild resources. In the southwestern and southeastern provinces, the planting way is more and more various. To perfect the planting way and to enhance the overall planting level better, the construction of GAP seems especially important. The lower foster cost of text tube plantlet during the process of production can be made better use during the research on the composition and pesticide effect of text tube plantlet of Dendrobium. This paper mainly covers:Ⅱ. Research on the regeneration system of text tube plantlet of Dendrobium. It introduces the selection of medium from callus to buds rooting, and the effects of hardening time, temperature, transplantation medium as well as transplanting methods on the survival rate of Dendrobium. It is1/2MS add IBA0.4mg/LN Banana Juice10%Sucrose2%、Paclobutrazol1.0mg/L that is the best text tube plantlet from the experiment. The best results is achieved when the text tube plantlet has been hardened for ten days at the temperature of25■2℃. Using broken wood, sphagna and bark as transplantation medium can ensure the survival rate of Dendrobium more stable. It is concluded that the survival rate and the growing condition of group-planting excels that of per-planting from several comparative experiments, which demonstrates the group effect provided by Dendrobium.Ⅱ. Research on the comparison between the text tube plantlet of Dendrobium and the chemical composition of cultivated plant. The paper discusses protein, amino acid and the contents of trace elements. Experiments show that the contents of protein is reduced with the increase in the numbers of planting years. Besides, the contents of protein in leaves is higher than that in stem and the contents of protein in the text tube plantlet of Dendrobium is higher than that in the cultivated plant. As for the composition of amino acid, both the text tube plantlet of Dendrobium and the cultivated plant covers all the essential amino acid and semi-essential amino acid in human body. What’s more, the contents of amino acid in the text tube plantlet of Dendrobium is superior to that in the cultivated plant and the contents of trace elements is also higher.III. Research on the comparison of pharmacological effect between the text tube plantlet of Dendrobium and the cultivated plant. It studies the function of cancer cell and the role in improving immunity of the text tube plantlet of Dendrobium and the cultivated plant comparatively. Through the cytotoxicity experiments (MTT), it is proved that the inhibition rates of ethanol extract (256mg/L) in the group of the text tube plantlet of Dendrobium and the cultivated plant on human breast cancer cells (MCF-7) are separately61%and57%and the positive control group (Five-fluorouracil50mg/L) is72%. Finally, it is concluded that Dendrobium has a significant role in inhibition of cancer cells. During the detection of apoptosis, the apoptosis rate in group of Dendrobium (256mg/L) is18.78%, in the group of text tube plantlet (256mg/L) that is15.00%, and in the positive control group (Five-fluorouracil50mg/L) that is38.20%. As a result, the cancer cell inhibited by Dendrobium is proved to be apoptosis. During the testing of reactive oxygen species, the mean fluorescence intensity in blank control group is70, that in the group of the text tube plantlet of Dendrobium is91.65, and that in the group of the cultivated plant is102.69. It is concluded that Dendrobium’s inducing apoptosis is related to the improvement of intracellular reactive oxygen species. In vivo tests, both the text tube plantlet of Dendrobium and the cultivated plant can improve the mice’s organs index (Thymus, Spleen) significantly. The experimental results are as follows:The group of Dendrobium (Thymus2.664+0.815mg/g, Spleen4.206±0.928mg/g); The group of the text tube plantlet of Dendrobium (Thymus2.916±0.597mg/g, Spleen3.962+0.417mg/g)Ⅳ. Construction of GAP of Dendrobium. It studies the launch of the construction of GAP and the selection of the planting base. The paper puts forward some viewpoints and suggestions about the problems during the construction that are:1. Policy support and the increase of certification costs can carry out the construction of GAP effectively.2. Good communication among enterprises, farmers and research institutes can ensure the quality and the output.3. The balance between the quality and the output during the process of planting needs to be controlled strictly.4. The combination of biological control and pesticides control can restrain pests and diseases of Dendrobium reasonably.