| Genus SeIaginella P. Beauv subordinated to Selaginellaceae is a sole genus inthis family. There are about 700 species in Selaginella worldwide, about 60～70species in China, and 22 known species are used as traditional or folk medicines.Among them, the 14 medicinal species are found in Hubei Province, China.Selaginella plants generally contain a variety of biflavones, mainly amentoflavone,which are probable active substances for anti-cancer. Some species cantain alkaloids.The modern researches showed that these herbal medicines have extensivepharmacological activities, such as anti-cancer, anti-virus, anti-bacteria,hypoglycemic effect, stopping bleeding and immunoregulation, etc.. Among themthere are several species which have been recorded or registered in the drug standardspublished by the nation or the local government. However, most of them still lackmethods for authentication and quality control so far, and it is difficult to identifysome species in this genus. Thus, in this thesis systematic pharmacognostic study wasmade on the 10 medicinal species of Selaginella in Hubei with methods as toxonomy,anatomy, TLC, IR, NIR, HPLC and RAPD techniques, contents of the activesubstance amentoflavone were determined by HPLC, and relationships among thesespecies were explored, so as to guide the clinical application and the quality control.According to the wild survey and study, the author found the actual number ofSelaginella speices in Hubei is 15 and the medicinal species is 14 (the number of theliterature record is 13 and 10), found that Selaginella heterostachys is a new recordspecies in Hubei, and put forward that the variable type of S. delicatula should betreated as a variety because of the differences in the plant appearance, anatomicalstructure of the stem, IR spectrum and HPLC fingerprint.Several techniques and mothods were employed in identification study, including morphology, histology, TLC, IR and HPLC. The results showed that thereexris both the general characters and the characteristics at the various levels, by whichthe 10 species of Selaginella could be identified. The 10 Selaginella plants have somegeneral anatomical features such as sclerenchyma, air chamber, cross-bridge,pericycle, etc., but all the species can be distinguished from each other by severalmicroscopic parameters, namely, number of layers of thick-walled cells, number ofair chambers and its/ their shape and size, number of thin-walled cells as well asnumber of rows of these cells forming cross-bridge. The TLC results of the 10 herbalmedicines showed that each cantains amentoflavone, but the number, location, sizeand shade of the spots vary from species to species. The IR spectra of the 10 speciesof Selaginella obtained by a FTIR spectrometer showed that there generally are the 11common absorbing peaks (cm-1): 3418±4, 2927±3, 1740, 1648±2, 1513±3,1428.5±0.5, 1383.5±0.5, 1242, 1156, 1046±3 and 670. But all the species can bedifferentiated from each other according to infrared spectral patterns as a whole, thenumber and wave-number (λmax) and the height of the absorption peaks, especiallythe these charactristics at the fingerprint zone (1250cm-1-400cm-1). HPLC fingerprintsof 10 Selaginella species were established with amentoflavone as a reference material,among them exist 4 common peaks whose relative retention times are 0.118, 0.166,1,1.052. But each species has its own particular peaks, or has its characteristic naturebased on all the peaks as a whole. The HPLC fingerprint chromatograms can be usedin authentication of all the species and in their quality analysis as well. What more,the results of RAPD analysis of the 8 different species of Selaginella also showed thedifferences among these plants.The contents of amentoflavone in the 10 Selaginella species (13 samples) weredetermined by HPLC, the contents are more or less-higher than 1.0％in S.sinensis,S.nipponica and S. moellendorffii, but somewhat or significantly less than that inS.delicatula, S. uncinata, S. labordei and S. heterostachys. It was also found thathabitat of the plant is one of key factors to affect content of the chemical ingredient.The relationships among the most Selaginella species could be deduced by thedegree of similarity of the anatomic characteristics, IR and NIR spectra, TLC, HPLC fingerprint chromatograms and RAPD marks, especially by the results of clusteranalysis of NIRS and RAPD, and overlap for the HPLC peaks as well. Nearly all theinformetion obtained through above various techniques or methods showed there areclose relationship between S.tamariscina and S.pulvinata, among S. labordei, S.heterostachys and S. nipponica. These all are in accordance with the results deducedby the classical taxonomy. Beside, according to the TLC result and the clusteranalysis of NIRS and RAPD, a closer relationship should also exrist betweenS.delicatula and S. maellendorffii. All the above inferences indicated it is reasonablethat S. pulvinata and S. tamariscima are used as the same medicinal material"Juanbai", and S. delicatula and S. maelIendorffii have the similar applycation in folkmedicines.In short, the above-mentioned researches would provide systematic methods aswell as theory basis for classification and identification of the medicinal plants,control and analysis of quality of the herbal medicines, and rational use of theresources from Selaginella.
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