Studies On Liquid Fermented Physiological Aharacteristics And Dynamic Model Of Phellinus Linteus

Phellinus is a valuable medicinal fungus used as anti-cancer and cancer radiotherapy and chemotherapy drugs in the field of clinical medicine at present.The natural wild Phellinus resources are scarce and the production of artificial cultivation cannot meet the demand for medication.Foreign countries produce large-scale Phellinus linteus and secondary metabolites by liquid fermentation technology,but it is still rest on the shake flask stage on the laboratory in China.Industrialized fermentation is rarely commercialized because there is little research on its species characteristics and metabolic law of fermentation process.Therefore,in this study,the molecular biology techniques and response surface analysis methods were used to select the excellent characteristic of Phellinus linteus and optimize the liquid fermentation process,at the same time,the physiological characteristic and metabolic regularity of the fermentation process were studied.The following results were obtained:1.In this study,rDNA ITS sequence analysis were used to identify six species of Phellinus linteus which were collected and introduced in the field.Then,the result showed that mulberry-W,mulberry-F,mulberry-D,mulberry-Y,mulberry-H5 strains belonged to Inonotus linteus(Also known as Phellinus linteus),Mulberry-H1 belonged to Fuscoporia qilva.Mulberry-H was selected for its good growth performance and medicinal value,its growth rate of mycelial flat culture mycelium was 4.39±0.15mm/d,mycelial biomass was 14.63±0.31g/L and the production of extracellular polysaccharide was 5.20±0.05g/L in shake flask culture.2.The fermentation was optimized by Plackett-Burman experimental design and response surface analysis.The result showed the optimum fermentation condition included:corn flour 10.86g,peptone 5.35g,KH2PO4 1.63g,glucose 10g,yeast extract 2g,MgSO4·7H2O 1g,VB110mg,water 1000ml.Under this condition and after 8-days shake cultivation,the biomass was 21.876±0.62g/L,increased by 36.98%compared with before;the yield of extracellular polysaccharide reached to 6.502±0.04g/L,which was increased by 12.30%compared with before.When the initial pH was 6.0 and the liquid volume was 120ml/300ml and the inoculation amount was 12%and the shaking speed was 200r/min and the temperature was 28 ?,the average yield of mycelial biomass was 22.38±0.21 g/L and the polysaccharide was 6.54 ± 0.02g/L.3.Physiological characteristic of liquid fermentation of Phellinus linteus was studied.The results indicated that the mycelium growth process was divided into four stages:retardation period,logarithmic growth stage,stable period and extinction period.The fermentation period was 192h,the maximum mycelial biomass was 22.49±0.56g/L and the maximum exogenous polysaccharide yield was 6.56±0.03g/L.Based on Logistic equation and Luedeking-piret,the kinetic models of mycelia growth,exo-polysaccharide production and substrate consumption were obtained,which provided a reasonable regression with test data.The extracellular enzyme activity in liquid fermentation of Phellinus linteus was studied,and the results showed that the order of the carbon source in the culture medium was as follows:starch>cellulose>lignin.Proteases were induced by the use of nitrogen-like protein substances.4.The enlargement test of 20L fermentation tank was done,and the results showed when the initial pH was 6.0 and the loading volume was 70%and the inoculation amount was 12%and the culture temperature was 28? and the stirring speed was 200 r/min and the air flow rate was 6 L/min,the fermentation rate of mycelium and extracellular polysaccharide were 27.80± 1.26g/L and 6.98±0.15g/L;The growth characteristics and main physiological indexes of the 20L fermentation tank were basically same as those in the shake flask culture.The time of release could be judged by the law of change summarized by monitoring the pH value and the reducing sugar concentration of the fermentation broth.This study provides a theoretical and experimental basis for industrial fermentation of Phellin us linteus,can meet the clinical needs of Phellinus Linteus medicine and is significant to prot ect natural resources.