Effects Of Culture Conditions On Mycelial Growth And Polysaccharide Synthesis Of Polyporus Umbellatus

Polyporus umbellatus（Pers.）fries is a medicinal fungus of Polyporaceae.It is a traditional Chinese herbal medicine.Polyporus polysaccharide is an important active substance in P.umbellatus.It has anti-tumor activity,anti-oxidation,and the regulation of immunity.In recent years,Chineses medical industry has been growing steadily,especially the Chinese medicine industry is developing rapidly.So,people pay more attention to the application of traditional Chinese medicine.With the discovery of pharmacological studies of P.umbellatus,it has been used widely in clinical practice.Therefore,the demand for P.umbellatus is on the rise.However,the biological characteristics of P.umbellatus are not fully understood.Artificial semi-wild cultivation of P.umbellatus takes a long time and produces a low yield.Bag culture and liquid culture of P.umbellatus have the advantages of low cost and rapid proliferation.Therefor,it is an important direction for the future development of P.umbellatus.In this study,P.umbellatus was cultured under different conditions.To explore the effects of culture system on the growth and polysaccharide synthesis of P.umbellatus.In order to provide the basis for the industrial production of polyporus polysaccharide.The main conclusions are as follows:1.Drought stress affected mycelial growth and polysaccharide synthesis of P.umbellatus.The mycelial biomass,activities of polysaccharide synthesis related enzymes and polysaccharide content of P.umbellatus were higher under 100 g·L^-1PEG-6000treatment.P.umbellatus has a certain drought resistance,moderate drought stress can promote mycelial growth and polysaccharide synthesis.2.Adding mineral elements to liquid culture highly affected mycelial growth and polysaccharide content of P.umbellatus.When the concentration of K⁺is 10 mmol·L^-1,it is more advantageous to mycelial growth and polysaccharide synthesis of P.umbellatus.When the concentration of Ca²⁺is 5 mmol·L^-1,it is more advantageous to mycelial growth of P.umbellatus.When the concentration of Ca²⁺is 10 mmol·L^-1,it is more advantageous to polysaccharide synthesis of P.umbellatus.When the concentration of Mg²⁺is 10mmol·L^-1,it is more advantageous to mycelial growth and polysaccharide synthesis of P.umbellatus.When the concentration of Mn²⁺is 0.10 mmol·L^-1,it is more advantageous to polysaccharide synthesis of P.umbellatus polysaccharide3.In liquid culture,polyporus polysaccharide content and polysaccharide synthesis-related enzymes（HK,GPI,α-PGM,UGPase,UGE,FBP）activity were related to K⁺,Mn²⁺addition time and carbon source types.Adding K⁺at 4 d and Mn²⁺at 3～4 d were more beneficial to the polysaccharide synthesis of P.umbellatus.Sucrose as carbon source is more conducive to the polysaccharide synthesis of P.umbellatus.4.Mineral elements can affect the mycelial growth rate,colony morphology and mycelial morphology of P.umbellatus in solid culture.Suitable concentration of K⁺,Mg²⁺can promote the mycelial growth of P.umbellatus,and make the P.umbellatus mycelial enter the rapid growth stage ahead of time.Adding Mn²⁺could promote the secretion of pigments from the P.umbellatus mycelia.Adding Ca²⁺can promote the formation of mycelial bulb of P.umbellatus.The mycelial growth of P.umbellatus was greatly influenced by carbon sources.When fructose was used as carbon source,P.umbellatus mycelia grew faster,and when starch was used as carbon source,P.umbellatus mycelia were easy to form mycelial bulb.