Preparation And Bioactivity Analysis Of Gomphidius Rutilus Polysaccharides

Gomphidius rutilus is a famous edible fungus in the northeast ofChina. Because its fruiting body can not be obtained by culturedartificially, the development and exploitment of G. rutilus is greatlyrestricted. The mycelia can be gotten through submerged fermenttechnique. In this study, G. rutilus mycelia polysaccharides （GRMP）was prufied and its biological activities was also studied based on theoptimal culture medium and conditions of liquid fermentation for themycelia production and the confirmation of GRMP optimal extractionconditions. It will give foundation for further development andutilization of GRMP.Firstly, the optimized culture medium determined according tosingle factor and orthogonal experiment, the optimized culture mediumis shown as follows: sucrose30g/L, peptone3g/L, MgSO₄0.5g/L,K₂HPO₄1.5g/L, KH₂PO₄0.2g/L, ZnSO₄0.03g/L and MnSO₄0.03g/L.Fermenting with the medium, the mycelia yield can reach8.66±0.26g/L, which is as1.5times as pro optimization. The optimal culturalconditions are as follows:12.5%（v/v） seeds of fermentation brothinoculated in200mL medium （pH9.0） which is loaded in500mL flask,and the medium are cultivated with180r/min at28℃for7days. Inthis condition, the yield of mycelium can reach9.32±0.15g/L.The mycelia polysaccharide was extracted with hot water digestionand alcohol precipitation. The optimal extraction technology conditionsfor response surface design are displayed as follows: extractiontemperature is95.44℃, extracting time is2.86h, the ratio of water to raw material is1:20.02, extraction times is3. In these conditions,crude polysaccharide extraction yield can reach17.69%（w/w）.Act as freeze thawing, protease, sevag, and DEAE-CelluloseDE-52ion exchange chromatography, two components, GRMPW andGRMPS, were purified form GRMP. And then Sepharose CL-6B gelchromatography was used to further purify GRMPW and GRMPS.Each of them was only get one component which has great dispersity. Itmeans both them has a wide molecular weight distribution. UV was useto test all the components, and there were no protein absorption peaks.IR result showed that GRMPW and GRMPS have formyl group andsulphate ions, it indicates that these polysaccharides have somebiological activities. HPLC results showed the monosaccharideformation of GRMPW and GRMPS are both glucose and xylose, theircomposition proportions are0.46:1and0.43:1, respectively. And thecontents of two kinds of monosaccharide of GRMPS were higher thanthat of GRMPS.Antioxidant activity, antitumor activity and lymphocytetransformation ability of GRMPW and GRMPS in vitro were studiedsuccessively. The results showed that GRMPW and GRMPS can partlyclear the superoxide radical, hydroxyl radicals and DPPH free radicals.The effect of GRMPW to hydroxyl radicals is the most remarkable. Theother clearing effects and reducing power are relatively lower. Thestudy also showed that fewer antitumor activities in vitro. GRMPW andGRMPS can obviously promote multiplication of lymphocyte, and theeffects with ConA are not distinct.