The Research Of The Fermentation Of Armillariella Tabescens And Antioxidant And Antibacterial Activity Of Polysaccharides

Armillariella tabescens(Scop.ex Fr),commonly called “Liang Jun”,belong to basidiomycotina,false armillaria genera.The polysaccharide which was isolated from Armillariella tabescens has been demonstrated having broad application prospect for its unique activities such as antibacterial,antioxidant activity,inhibition of tumor growth,immunomodulation.With the progress of liquid fermentation technology,more fungi had been cultured with the method of liquid fermentation.This research focuses on studying the liquid fermentation process optimization and its antibacterial activity and antioxidant activity.The main findings are as follows:The suitable carbon and nitrogen sources were first research in liquid fermentation process.The results showed the best carbon and nitrogen sources were corn flour and yeast extract.On the basis of single factor test and orthogonal design optimization,this paper researched the effect of speeds,temperature,culture time,liquid volume and other conditions on liquid fermentation.From the study,the optimum conditions for liquid fermentation: The cultivation conditions were optimized as temperature as 24?,250 mL shake bottled liquid volume 130 mL,speed 150 rpm respectively and culture ten days.The other effects of different fermentation condition for submerged fermentation are initial pH,calcium ion concentration and sugar concentration.Our experiments results showed the best initial pH,calcium ion concentration and sugar concentration were 6,0.5% and 3%.In antioxidant and antibacterial activity of Armillariella tabescens polysaccharides experiments showed highly effective antibacterial activities against Escherichia coli(E.coil).Results showed that polysaccharides had effective antibacterial activities.The MIC of polysaccharides is 19.6±0.31 ?g/mL for E.coli.Moreover,SEM investigation indicates that the polysaccharides changed the morphology of E.coli.Mechanisms of cell integrity study through change of cell membrane,wall and enzyme by SEM experiments.Through morphological changes in E.coil,mechanisms are examined for bacterial damage caused by polysaccharides.This experiment of test the antioxidant activity of polysaccharides had been verified.And the polysaccharides had the total restoring force and DPPH Free radical scavenging activity.