| Cordyceps (Cordyceps militaris (L.) Link.) is an important medicinal herb in traditional Chinese medicine. It is also an alternative of valuable Chinese medicine of Cordyceps sinensis. Cordycepin and cordycepic ploysaccharide are two main biologically active substances of Cordyceps. Cordycepin has anti-tumor, anti-bacterial and other biological activities, and cordyceps polysaccharides have enhancing immunity, anti-oxidation and other biological activity. Although many extraction, separation and purification methods have been constructed, the efficiency of extraction and purification still is not high enough for large scale industrial productions. So it is needed to construct flash-type extraction and other high efficient extraction and purification methods. The chromatographic characteristics are reliable conditions for quickly identification of cordycepin. So the ultraviolet, infrared spectroscopy, NMR spectrophotometry of cordycepin was systematically studied. Although the functions of inhibition of cordycepin have been studied by other researches, the inhibition of cordycepin on gastric tumor was not studied before. So the inhibition function and inducing apoptosis ability of cordycepin on gastric BGC-823 were studied.Fruiting bodies of cordyceps were used as materials, four factor and three levels orthogonal tests were done to build up the optimal extraction technology of returning extraction and flash-type extraction for cordycepin and cordycepic ploysaccharides. Then, the two extraction methods were compared under optimal technologies. It was found that the optimal technology for returning extraction was 25% ethanol,extraction for 2.5h, extraction for 2 times and liquid ratio at 30:1. and that of flash-type extraction was distilled water, extraction for 3min, liquid ratio at 35:1 and pH at 3. Under optimal conditions of both, flash-type extraction hold the advantage of shorter extraction time (1:30),higher extraction yield ratio (0.263%: 0.150%), and saving energy and reagents. Because the biological activities of the extracted materials remain well and the extraction speed was elevated this method not only suitable for the extraction of cordyceps but also for the components sensitive to heat or easily decomposed materials.The separation and purification technology conditions of cordycepin were also built up through alcohol precipitation, extraction and silica gel column chromatography. And the cordycepin monomer was gotten, the purity of cordycepin reached 98.8%. The separation and purification technology conditions of cordycepic ploysaccharides were also built up through alcohol precipitation, extraction.For the purpose to build up more accurate cordycepin identification method the ultraviolet spectrum, infrared spectrum and NMR spectrum of cordycepin were characterized. And the characterization of cordycepin for ultraviolet spectrum, infrared spectrum and NMR spectrum was built up.At last, the inhibition of cordycepin on tumor and the induction of cordycepin for the apoptosis for gastric cancer cells were studied. It was verified that cordycepin had the inhibiting abilities for gastric cancer cells BGC-823. And cordycepin could induce the apoptosis of BGC-823 cells verified by Hoechest staining, DNA ladder and other methods. |
