Medicinal Identification System

Herba Dendrobii(Shi-hu) is the fresh or dried stem of Dendrobium nobile, D. candidum(D. officinale) or D. fimbriatum var. oculatum(D. fimbriatum) and their allied species according to the Chinese Pharmacopoeia(2005) for nourishing"Yin"and clearing heat. Now there are more than 50 kinds of medical Dendrobii used as"shi-hu", but some other species are also used as medical Dendrobii in the circulataion of commodity and clinical application, including the plant of Pholidota, Bulbophyllum and Flickingeria of Orchidaceae etc. It has harmful effects in the clinical effect and the safety of the application. The writer presume that the imperfect identification methods of medical Dendrobii is the main cause of these confusions. Therefore this research had a systemic investigation on 42 kinds of Dendrobium(Shihu) and their adulterants used in our country by mesans of character and micro-identification, IR, HPLC, DNA molecular identification, and then used synthesis identification to establish a platform and supply a good device of identifying medical Dendrobii and their adulterant . The main findings as follows:(1) The results of character identification revealed that there are 7 specific identification characters among the 16 ones, which are the shape of stem, the branch of the stem, the texture of the dried, the leaves and vaginas covering with black floss, the vagina's cascade, the shape of the leaf, and the stripe of the vagina. This method can identify 21 kinds of medical Dendrobii and their adulterants, such as D. nobile, D. fimbiatum and D. harveyanum etc.(2) The results of microscopical identification indicated that the identifying meaning of 17 characters in 22 microscopical characters are outstanding such as the size and the type of sclerosis of epidermal cell, the size and thickness of stratum subcutaneum cell, the calcium oxalate of prism and acicular crystal and the cluster silicon crystal ect. The method can identify 16 kinds of medical Dendrobii and their adulterants such as D. fimbriatum, D. nobile and D. williamsonii. This paper corrected and replenished the microstructure of D. nobile and D. fimbriatum, and described the microstructure of cross section of the other 8 kinds of medical Dendrobii and their adulterant which are not reported. They are D. jenkinsii, D. brymerianum, D. Stuposum, D. pendulum, D. guangxiense, D. trigonopus, D. sp. cv. and Bulbophyllum odoratissimum.(3) The results of IR identification revealed that there are profuse IR fingerprint characters among the 42 kinds of medical Dendrobii and their adulterants. The total IR fingerprint peaks of them are 493 and the average are between 9 and 15 in every species; the IR fingerprint peaks of extractive of chloroform are 708 and the average are between 10 and 28. The analytic result indicated that this method of identification can be used to identify 32 kinds of medical Dendrobii species and their adulterants. And IR can be used in drug action composition's superficial syndrome and offer evidence to quality evaluation of medical Dendrobii as well as.(4) Among 42 kinds of medical Dendrobii and their adulterants we choose 7~15 HPLC chromatographic peaks as HPLC identification characters for them. The results indicated that this method can identify 40 kinds of medical Dendrobii including 3 kinds of medical Dendrobii which in the Chinese Pharmacopoeia(2005).(5) We have sieved 5 RAPD random primer to analyze 41 kinds of medical Dendrobii and their adulterant. The results showed that the 5 random primers amplified 222 polymorphic loci, the average of polymorphic loci are among 12～26. The results indicated that the RAPD molecule mark identification method can identify 39 kinds of medical Dendrobii and their adulterants.(6) We have sieved 8 kinds of EcoRI and MseI selective primers to analyze 41 kinds of medical Dendrobii and their adulterants. The results showed that the 8 kinds of AFLP selective primers are amplified 1648 loci, among them there are 1643 polymorphic loci and 107 special straps. The analytic result indicated that the method of AFLP molecular identification can identify 39 species medical Dendrobii and their adulterant. The result of the AFLP identification of a unkonwn sample (DSP.) indicated that the method refer to the DNA molecular identification of medical Dendrobii which other method hard to identifyed.It indicated that the 5 methods could not completely identify 42 kinds of medical Dendrobii and their adulterants. So this paper based on the synthesis estimate of 5 identification methods to establish the synthesis identification of medical Dendrobii. It can apply a feasible technique and method to identify medical Dendrobii.(7) We have set up the search database of medical Dendrobii initially by Access database software through the data of character, micro-identification, IR and DNA molecular identification which has fast speed, convenient operation, and it can also be unfolded with ASP application program and long range access through network. It is an application platform for identification to share together.(8) The contents of polysaccharides of D. loddigesii in different growth stages (one year, two years and three years) are 18.45%,23.54% and 15.71% respectivly, and the total content of polysaccharides of D. loddigesii from five areas lies between 12.21 and 22.62%, average 17.80%. The contents of polysaccharide of 39 kinds of medical Dendrobii are between 7.69%～24.13%, and the average is 15.56%. Among them, D. officinale has the highest content(24.13%), while D. acinaciforme has the lowest(7.69%). All of these revealed that there is obviously difference on the contents of polysaccharide among medical Dendrobii and their adulterants. The polysaccharide assaying of different species can offer reference to the formulating of quality criteria of medical Dendrobii.