Isolation And Hypoglycemic Effect Of Polysaccharide From Bjerkandera Adusta

Bjerkandera adusta belongs to Polyporaceae.The report on the biological effects of Bjerkandera adustais is about its antitumor activity.However,the hypoglycemic activity of the polysaccharide from the Bjerkandera adusta was less reported.This study isolates the laboratory strains of fungi in the laboratory,studying on the species identification,active polysaccharide extraction and hypoglycemic effect,the main results are as follows:1.The fungus is identified as Bjerkandera adusta after ITS sequencing and BLAST.2.The weight of dry mycelia and polysaccharide content are taken as indexes to optimize liquid fermentation culture medium components:lactose 20 g,yeast extract powder 3.5 g,MgSO4·7H2O 1 g,KH2PO4 2 g,peeled potato 100 g,H20 1L.3.The weight of dry mycelia is taken as index to optimize the best fermentation conditions:pH 6,8 d of culture time,revolving speed 160 r·min-1,initial inoculuminitia 8mL,culture volume 100 mL/250 mL.4.In order to explore the ultrasound-assisted procedure for the extraction of water-soluble polysaccharides from submerged-cultured mycelia of Bjerkandera adusta,basing on the single factor experiment,the study choosess water material ratio,ultrasonic time,ultrasonic temperature as impact factors,apply response surface method Box-Behnken center combination test and level,regards polysaccharide extraction yield as response value,optimizes the ultrasound-assisted extraction conditions for further.Studying and discussing the optimum levels of factors and their interactions,build the quadratic multinomial model which affect the mycelia polysaccharide extraction yield:Y = 8.56-0.02X1-0.25X2 + 0.27X3 + 0.080X1X2 + 0.010X1X3 0.025X2X3-0.66X12-0.54X22-0.42X32.The statistical analysis indicated the independent variables(X1?X2?X3),the quadratic terms(X12?X22)has significant effects on the yield of polysaccharides(p<0.01)and the interaction between X1 and X2 has significant effect on the yield of polysaccharides(p<0.05).According to the results of regression analysis to get the best process conditions for polysaccharide ultrasound-assisted extraction:48:1 of ratio of water to ried mycelia,a time of contact of 27 min,56?.Under these conditions,the experimental yield of polysaccharides was 8.57%.5.Preparing polysaccharides into different concentrations and determine the effect of scavenging rate of DPPH.The scavenging rate is maximum 73.39%when the concentration is 1.5 mg·mL-1.6.Using IBMX+DEX+Insulin to induce 3T3-L1 preadipocyte to be dipocyte.Building Insulin resistance cell model of 3T3-L1 adipocyte cells with 3 ?mol/L DEX.MTT test finds that there is non-toxic side effects of polysaccharide.Glucose oxidase method detects the supernatant and finds that polysaccharide has a hypoglycemic active.7.In order to characterize the molecular morphology of polysaccharides from Bjerkandera adusta,Raman spectra and scanning electron microscopy were performed.The Raman spectra of polysaccharide were tested by 532 nm laser light source.The 440 cm-1 peak appeared in the spectrum showed that the polysaccharide containing glucose.By using the scanning electron microscope,the polysaccharides of different forms of polysaccharides in different times of the objective lens were different.Under the 200 ?m objective lens,the polysaccharides can be seen in the form of dead leaves,rough surface while the polysaccharides has an irregular shape under the 50 ?m objective lens.Under the 5 pm objective lens,the main rules of polysaccharides were regular broad bean,small ball shape and smooth surface.