Studies On Chemical Constituents And Quality Control Of Gastrodia Elata

Gastrodia elata Blume (Tianma in Chinese), a popular Chinese herb medicine, has been used for many years as an anticonvulsant, an analgesic and a sedative against vertigo, general paralysis, epilepsy and tetanus. This dissertation describes the isolation and characterization of chemical ingredients of Gastrodia elata by traditional preparative methods, together with preparative HPLC and HPLC-DAD-MS. The main research results are as follows:Phytochemical investigation of primary fractions GE-2, GE-3, GE-4, GE-6, GE-7 and GE-8 led to the isolation and identification of 24 compounds, of which ten compounds were isolated from this plant for the first time and one compound was new compound. These pure compounds with devised structural types provided sufficient reference compounds for further HPLC-DAD-MS analysis.Based on studies of ten representative reference compounds, an efficient HPLC-DAD-MS method was developed for identification of predominate phenolics, together with attractive minor nucleoside analogues and amino acid derivatives from ethanol extract of Gastrodia elata. As a result, 16 phenolics, 6 nucleoside analogues and 8 amino acid derivatives were identified. Among them, 13 compounds have not been reported yet. These suggested new compounds will be beneficial for further target isolation.Phytochemical investigation of target fraction GE-5 led to the isolation and identification of eleven compounds, of which three compounds were isolated fromthis plant for the first time and five compounds were new compounds. The isolation results indicated that the target isolation guided by LC-DAD-MS is an efficient method for new compound purification.In total, thirty-four compounds were isolated and thirty-two compounds were identified from Gastrodia elata. In which, six compounds were new compounds and thirteen were firstly reported structures in Gastrodia elata. Six new compounds comprise five parishins and one nucleosides, while the thirteen firstly reported structures comprise nucleosides, amino acids, and characteristic ingredients in Gastrodia elata and other Orchidaceous plants.For better quality evaluation of Gastrodia elata herb, an HPLC fingerprint chromatogram of Gastrodia elata was developed and the devised fingerprint processing methods were investigated. These devised fingerprint processing methods include the calculating of overlapping, ten strong peak and the calculation of similarity, together with hierarchic clustering analysis, principal component analysis and discrimination analysis. Combined with the determination of four indicative components, we tried to evaluate the quality of Gastrodia elata from different aspects.