Studies On The Preparative Technology And The Quality Control Of The Effective Fraction And Its Preparation From Rhizoma Dioscoreae Spongiosae

Based on the result that the 90% ethanol fraction of the water extract from the rhizomes of Dioscorea spongiosa showed obvious antiosteoporotic activity, the preparative technology and quality control methods of the effective fraction and its preparation were systematically studied in this thesis. Furthermore, the relevant studies on the preparative process and quality standards of the chemical reference substance---methyl protodioscin and the quality control methods of the medicinal plants were also included.1. Two major compounds were isolated and purified from the rhizomes of Dioscorea nipponica Makino by the combination of solvent extraction, macroporous adsorption resin chromatography, silica gel column chromatography and repeated recrystallization. Their structures were identified as methyl protodioscin and methyl protogracillin by compared with authentic substances, respectively. The sources, preparation procedure, structure elucidation, purity determination, content assay, stability, packet and storage of chemical reference-methyl protodioscin were investigated according to the requirements of chemical substance used as reference in the new drugs studies of Traditional Chinese Medicine.2. Thin-layer chromatography (TLC) and ultraviolet (UV) spectrum identification methods as well as determination methods about the content of total saponins and methyl protodioscin in the Rhizoma Dioscoreae Spongiosae were added on the basis of quality control methods recorded in Chinese Pharmacopoeia in force, which supplement and consummate the quality control methods of this medicinal plant in Chinese Pharmacopoeia.3. The optimum extraction technology was screened according to the factors which affected the extraction such as the magnitude of the powdered crude drug, the quantity of water added, soaking time, reflux time, extraction times, and centrifugation time with the content of total saponins and methyl protodioscin as indices. The purification procedure of the water extract by macroporous adsorption resin chromatography was systematically studied. The type of resin and the elution gradient were determined and some of indices that affected the purification effect such as specific amount of sample loaded, retention ratio, specific amount of adsorption capacity and relative elution amount were evaluated in the purification and enrichment procedure. In the consideration of two key factors -diameter-height ratio of column and elution rate which significantly affected the results of purification, the preparative technology of the effective fraction was finally confirmed by orthogonal tests and the content of total saponins and methyl protodioscin were chosen as markers.4. Considering the properties of the chemical constituents in the effective fraction, the dosage forms were screened and tablet was selected as the suitable form. Referred to the standards of medicinal tablets, the formula of tablets and its preparation technology were determined.5. Quality control methods including TLC, vanillin-perchloric acid colorimetry and HPLC were established to evaluate the quality of the effective fraction and its tablets. The quality standards of the effective fraction and its tablets were worked out according to the relevant requirements of new agents.