Study On Extraction,Structure Characterization And Antitumor Activity Of Polysaccharide From Hirsutella Sinensis Mycelium

Cordyceps sinensis is a kind of valuable medicinal fungi in China and has many kinds of functions. Polysaccharide of Cordyceps sinensis is one of the main pharmacological active ingredients. Polysaccharide of Cordyceps sinensis has many kinds of biological activity which are the antitumor, immunological regulation, antidiabetic and so on. Its biological activity is closely related to the structure of polysaccharide, and the structure of polysaccharide is very complex, so the research and analysis of the structure of polysaccharide lays a foundation for the study of its biological activity. This topic mainly researched Cordyceps sinensis which was preserved in our laboratory.The main content and the results of the research are as followings:The identification of strain took advantage of the solid cultivation. The activated strains cultured on PDA under the different temperature (16℃,18℃,20℃,22℃) for 30 days. Basis on size of colony diameter, it was determined that the strain growth optimal temperature was 18℃. Then the strain cultured on solid cultivation at 18℃ and observed morphological characteristics and size of colony, mycelium and conidium. It was determined that the strain was the asexual type of Cordyceps sinensis.The content of the polysaccharides from mycelium was 4.71%±0.09% by using the method of phenol-sulfuric acid. The content of adenosine and cordycepin from mycelium respectively was 3.47±0.31 mg/g and 1.32±0.19 mg/g by using the method of HPLC. The content of the cordycepic acid from mycelium was 8.50%±0.05%　by using method of ultraviolet spectrophotometer. The content of the protein from mycelium was 31.97%±0.08%　by using the method of Kjeldahl. The content of the fat from mycelium was 8.09%±0.89%　by using the method of soxhlet extraction. The results showed that the active components of the artificial cultured mycelium were similar to natural cordyceps sinensis, and their contents were consistent with the contents of natural cordyceps sinensis.Cordyceps mycelium was got by the liquid cultivation. And macromolecular polysaccharide (HSP-Ⅲ) of molecular weight uniformity was got by water extract-alcohol precipitation, isolation and purification. The content of sugar was 89.87%. Molecular weight of HSP-Ⅲ was 513.89 KDa. It showed that HSP-III was uniform polysaccharide without protein, polypeptide and nucleic acid by the method of ultraviolet spectrum scanning.The study analyzed the structure characterization of HSP-Ⅲ by using the automatic polarimeter, infrared spectrum and NMR, thin-layer chromatography, periodate oxidation and Smith degradation, GC, CD and other technical means. The results showed that HSP-Ⅲ was a-(1→3) glycosidic bond link of furan dextran glucan and that monosaccharide was mainly composed of mannose and galactose. HSP-Ⅲ could complex with Congo red and had (+) cotton effect of triple helical structure. Morphology of HSP-Ⅲ was flaky aggregate by crosslinking of chains and granular structure.Antitumor activity of mycelium polysaccharide was measured through the method of MTT. The result showed that worked best at 100μg/mL and 400 μg/mL and inhibition rate respectively were 79.04% and 78.17%, antitumor activity of HSP-Ⅲ was higher than the HSP-Ⅱ.