An Interpretation Of Ten Types Dendrobium In Yunnan Baoshan Area In The Perspective Of Pharmacognostics

Dendrobium is the largest orchidaceae except Bulbophyllum. It is classified as perennial herbaceous epiphytic plant, mainly grows in Yunnan, Guizhou, Guangxi, Guangdong, Hainan province and Taiwan area and so on. Particularly, there grows the most in Yunnan province. As one very ordinary Chinese medicinal material, Dendrobium is of great significance:on one hand, being used in making tea, medicinal liquor and medicated diet, Dendrobium, which can be directly consumed by human, has efficacy of tonifying stomach and promoting fluid, as well as nourishing yin and clearing heat; on the other hand, it is a nice kind of ornamental plants.With severe damage, the wild resource of Dendrobium is in a gradual depletion, whose supplies increasingly fail to meet the demand, and the artificial planting Dendrobium occupies the main supplies of market. Along with the diverse sorts of commercial medicinal Dendrobium, different standard for its use in various places cause the phenomena of abuse and excessive mixed usage. Yunnan Baoshan area is rich in resources of Dendrobium plants. Among which, Dendrobium devonianum, mainly planted in Longling County, is the one widely planted in Baoshan area. Relatively high value of Dendrobium candicum processed helps greatly enhance the local economic development in Yunnan Baoshan area, while many other types of Dendrobium are not so well known or even gradually deplete. With aims to protect the resources of wide Dendrobium and rationally widen its development, this thesis project conducts it’s a pharmacognostical study on ten common types of Dendrobium to meet the demands of strengthening Dendrobium identification as well as building the experimental basis for the development and utilization of Dendrobium plants resources in Baoshan area.Source identification, macroscopical identification, microscopic identification and TLC method are applied in the pharmacognostical study on ten common types of Dendrobium in Baoshan area, including Dendrobium longicornu Lind, Dendrobium nobile Lindl, Dendrobium chrysotoxum Lindl, Dendrobium wardianum Warner, Dendrobium devonianum, Dendrobium williamsonii, Dendrobium bellatulum Rolfe, Dendrobium moniliforme (L.) Sweet, Dendrobium thyrsiflorum and Dendrobium gratiosissimum. Through comparisons of their features of morphology, medicinal identification, physical identification of their stem tissues and powder, this thesis tabulates each identification character in several identification keys, for the convenience of further identification and consultation. Taking Dend-obine, Erianin and Dendrophenol as the reference substance, the experiments of this thesis project have got the basic information of the main chemical composition of the ten types of Dendrobium by TLC method. Identifying the ten types of Dendrobium by the above-mentioned methods, this thesis intends to provide experimental basis for the identification of Dendrobium.By high performance liquid chromatography (HPLC Method), a determination of the content of dend-obine and erianin in eight types of Dendrobium, involving Dendrobium longicornu Lind, Dendrobium nobile, Dendrobium chrysotoxum, Dendrobium wardianum Warner, Dendrobium devonianum, Dendrobium williamsonii, Dendrobium thyrsiflorum and Dendrobium gratiosissimum, displays that only Dendrobium nobile Lindl contains dend-obine, while erianin only exists in Dendrobium chrysotoxum, Dendrobium williamsonii and Dendrobium gratiosissimum. In the light of its simplicity, accuracy and reproducibility in its utilization, HPLC Method is an effective method for the quality control and identification of Dendrobium medicinal materials and their related preparation.