Purification,Bioactivities And Structure Analysis Of Cordyceps Sinensis Mycelium

Polysaccharide was one of the most important and abundant bioactive substances of Cordyceps sinensis,and also a research hotspot in the area of food chemistry.Optimization design of ultrasonic assisted extraction using the Box-Benhnken revealed the best condition was 32.2 min of extract time,507 W of extract power,29:1 of L/S ratio.Under the optimum extraction condition,the extraction ratio was13.8%.Three fractions named CSP40,CSP60 and CSP80 were obtained by gradient alcohol precipitation.Antioxidant assay showed good antioxidant activities of such three sections,and the order was CSP40>CSP80>CSP60.CSP40 showed the best antioxidant activity and the clearance rate was 61.0%of DPPH,99.6%of ABTS and 63.9%of hydroxyl radical.Antitumor assay showed certain cytotoxicity to A549 and CHL cells of such three crude polysaccharides which need further purification.Crude polysaccharide CSP40 was purified into two pure polysaccharides named CSP40-2a and CSP40-2bI.CSP40-2a and CSP40-2bI had a distinct advantage of the cytotoxicity over CSP40 and the CSP40-2a had better selective toxicity to A549 cell.Acetylation analysis by GC-MS indicated that CSP40-2a was composed of D-Mannose,D-Glucose and D-Galactose at the rate of 1.98:1.0:0.67.CSP40-2bI was composed of D-Mannose,D-Glucose and D-Galactose at the rate of 0.72:1.00:0.30.Methylation analysis of CSP40-2a detected 10 kinds of methylation products and methylation analysis of CSP40-2a detected 8 kinds of methylation products.A comparison between the two methylation revealed two different kinds methylation products and the different content.NMR analysis indicated the slight difference between the kinds of CSP40-2a,CSP40-2bI residues and quite difference of the content of the residues.CSP40-2bI contained the group of（?）R₂（R₁,R₂ and R₃ was unkown groups） but the CSP40-2a did not.