Studies On Extraction Process Of Gastrodin And Polysaccharides From Turber Of Gastrodia Elata

Gastrodia elata Bl. (GE) is a valuable herbal medicine which mainly used to deal with the diseases of cardiovascular and cerebrovascular system. It is essential and pregnant to study in-depth on GE and its related products with ascendant incidence of these diseases at present.Correlation research on the extraction and purification method on the effective component of GE was described with the letterpress. Above all, the optimum chromatographic condition was developed to analysis the GA in the sample.Following, we extract and separate gastrodin by immersing GE into ethanol. We discuss the effects to gastrodin extraction from medicinal materials particle size, extraction method and solvent, soaking time and extraction dosage. The optimum extracting conditions of gastrodin were as follows: 70℃, 8 times of 60% alcohol, extracting for three times, 1h each time.On GA in GE extraction, we study characteristic of separation and purification by TLC. The optimum puring conditions of gastrodin were as follows: Firstly, the suitable ratio of methanol and dichloromethane in the mobile phase was investigated preliminarily by thin-layer chromatography. The results show that the suitable ratio of mobile phase is methanol : dichloromethane=4:1 by volume, and the 100～200 mesh silica gel can be chosen as the stationary phase. Using above mentioned optimal operation conditions , the product purity of the column chromatography separation at room temperature was analyzed by HPLC (High-Performance Liquid Chromatography), and the result shows that the purity of gastrodin obtained can reach 65% . This separation system has many advantages, for example, great adsorption capacity, good backfill performance and cheap price.It has found that temperature was a very significant factor influencing the extraction rate of the water-soluble PGB and extraction time was a significant factor influencing the extraction rate of the water-soluble PGB through single factor experiment and orthogonal experiments. The optimum extraction parameters of WPGB were obtained: 60℃for extraction temperature, 2.5 hours of extraction time, 1:30 for the ratio of solid to liquid and 80% ethanol concentration and the amount of WAPG was about 12.86%.