Study On The Biotransformation Of Asiaticoside And Primary Phytochemistry Study Of Selaginella Doederleinii Hieron

Asiatic acid is a kind of aglycone of terpenoids in Centalla asiatica. The activity of glycoside has direct relationship with aglycone in Centalla asiatica through the research in recent years. In this study, asiaticoside was used as the substrate and reacted by glycosidase from microorganism to obtain asiatic acid.And then asiatic acid was isolated by silica gel column chromatography. The structure was examined by the method of NMR.In order to get a strain which could hydrolyse the asiaticoside to asiatic acid as much as possible, 3 strains were selected to study the ability of producting glycosidase. It confirmed Aspergillus niger is the best strain to hydrolyse the asiaticoside to asiatic acid.Moreover, the cultivate condition of Aspergillus niger was researched, in order to get asiatic acid as much as possible.It confirmed the optimization cultivate condition that pH was 5.0, cultivate time was 6 days, substrate concentration was 0.5%, glucose concentration was 8g/L, peptone concentration was 5g/L, KH2PO4 concentration was 5g/L, cultivation temperature was 28℃, MgSO4·7H2O concentration was 1g/L, MnSO4·4H2O concentration was 1g/L and NaCl concentration was 5g/L.Based on these conclusion, fermentation was scaled up in a fermentor.The result of optimized experiment was correspond with the result of shake flasks. It emonstrate that conclution is valuable.Selaginella doederleinii Hieron is a civilian herb which has been used in south of china usually. As a civilian herb, S.doederleinii has the function of eliminating wind, scattering frigidity, detumescence and treating cough. Flavanoid is the major chemical ingredients in the S. doederleinii.Chemical ingredients in S. doederleinii were studied. Multitude methods were used to isolate chemical ingredients of S. doederleinii, 20 chemical compounds were obtained. 12 chemical ingredients were identified on the basis of their chemical and physical properties as well as the data of NMR, combined with information from references. And and four chemical constituents(robustaflavone4',4'''-o-dimethyl ether,robustaflavone7,4',7''-o-trimethyl ether,Podocarpusflavone A,3β-Acetoxysitost -5-en-7-one) were obtained for the first timefrom this herb among the 12 chemical ingredients. The volatile oil of Herba S. doederleinii was extracted by steam distillation and analyzed by gas chromatographymass spectrometry (GC-MS). About 40 kinds of aetherolea compounds were identified. And obvious difference was found through comparison of the essential oil of S. doederleinii and other two kinds of Selaginella, Those differences have been generated on account of the disparity of species and might used to judge the genetic relationship in Selaginell.