Study On Pholidota Chinensis Lindl Polysaccharide And Chemical Constituents Of Ethyl Acetate Extraction

Pholidota chinensis Lindl, one kind of herbal medicine, is a member of orchid family. Its pseudobulb or the entire grass has great medicinal values, however, the studies on the functional components of it are really few. The reports about Pholidota chinensis Lindl polysaccharide which is one component of Pholidota chinensis Lindl are not found all over the world. This article mainly studied Pholidota chinensis Lindl polysaccharide's extraction, structure, nature and anti-oxidantive effect, and carried on the preliminary separation and analysis to the Ethyl acetate extraction part. The results of the experiment were as follows:1. The best extraction condition of Pholidota chinensis Lindl polysaccharide was that: the time of extraction was 5 hours, the ratio of sample to water was 1: 40 and the temperature of extraction was 80℃. Under the best extraction conditions, the extraction efficiency of the polysaccharide of Pholidota chinensis Lindl was 2.25 %. Two methods of eliminating protein were studied, and the salting-out method was better and more economical than Sevag's method.2. The Pholidota chinensis Lindl's total sugar content was determined, and the result was 3.352%. The molecular weight of Pholidota chinensis Lindl polysaccharide was determined by HPLC, and its molecular weight was 45200 Dalton. The Pholidota chinensis Lindl polysaccharide's intrinsic viscosity was 1.55 mL/g.Different molecular weight size of Pholidota chinensis Lindl polysaccharide was prepared by the ultrafiltration, and their intrinsic viscosity was determined separately by the Ubbelohde viscometer. It was discovered that their intrinsic viscosity reduced along with their molecular weight.3. Degraded the polysaccharide under 110℃with 2 mol/L Trifluoroacetic acid in a vacuum tube for different time (1 h, 2 h, 3 h, 4 h and 5 h, 6 h, 7 h, 8 h) to study the effect of degradation time on the degradation products. The effect was studied by TLC and HPLC. The result showed that the degradation time had a certain influence on the the degradation products.After HPLC, IR and NMR analysis, it was showed that the Pholidota chinensis Lindl polysaccharide was mainly constructed by mannose throughα-1, 4 - glucoside bond.4. The effect on scavenging·OH and·O^2- of Pholidota chinensis Lindl polysaccharide was studied by Fenton system and Pyorgallol Autoxidation Method respectively. The results showed that: the Pholidota chinensis Lindl polysaccharide had a good anti-oxidantive ability; the ability increased along with the density; the crude polysaccharide's ability was stronger than the purified polysaccharide's, but their ability was all stronger than or equal to Vc's.5. After chemical constituents' pretesting experiment, it was discovered that the components of Pholidota chinensis Lindl included Sugar,Amino acid,Protein,Phenols,Tannin,Cardiac glycosides,Steroid,Terpene,Organic acid and Saponins.The Ethyl acetate extraction part was analied by TLC, the results showed that when the developing solvent was Cyclohexane: Carbon tetrachloride: Ethyl acetate =1:1:1, after launching the coloration, 6 spots were obtained, moreover the separation effect was best.The Ethyl acetate extraction part was analied by silica gel column chromatographic. A white crystal was obtained, and its IR map demonstrated that there were possibly -OH and -COOH in its structure. In addition, three components were obtained in part 28 - 63, two pure materials were obtained in part 64- 68.After TCA and HPLC analysis, four materials were obtained from A spot of Ethyl acetate extraction part; six materials were obtained from B spot of Ethyl acetate extraction part.