Hypoglycemic Effects Of The Exopolysaccharide From Submerged Culture Of Grifola Frondosa By Addition Of Rhizoma Gastrodiae Extracts

Grifola frondosa is a medicinal and edible fungus.that has the effect of enhancing immunity.It is mainly distributed in Sichuan,Yunnan,Guangxi and Fujian et al.This paper mainly carried out the research on the hypoglycemic effects of the Fermented filtrate and exopolysaccharide from submerged culture of G.frondosa by addition of Rhizoma gastrodiae extract.Determination of ?-glucosidase inhibitory activity by in vitro and on Alloxan-induced diabetic mice were used to test the hypoglycemic activity of exopolysaccharide from submerged culture of G.frondosa by addition of R.gastrodiae extract.This provides a theoretical basis for the development and research of the functional food of G.frondosa exopolysaccharides.The specific results are as follows:(1)The purpose of this study was to develop a method for decolorization of G.frondosa exopolysaccharides.Based on decolorization rate?polysaccharide retention and the ability of ?-glucosidase inhibition in vitro,the activated carbon,hydrogen peroxide and macroporous resin were used to decolorize the exopolysaccharide from G.frondosa.The results show that the resin is superior to the others.On the basis of one-factor-at-a-time,orthogonal array design method was used to optimize decolorization conditions.The optimal decolorization parameters for the exopolysaccharide of G.frondosa were decolorization temperature 55 °C,decoloration time 420 min,decolorization pH 5.0,and mass concentration of crude polysaccharide 10 mg/mL.Under the optimum decolorization conditions,the decolorization rate of G.frondosa exopolysaccharides was 90.61%,and the retention rate was 78.23%.(2)R.gastrodiae extract of different concentration were added into the fermentation system of G.frondosa.the content of GA,HBA and HA in R.gastrodiae extract was determined by High Performance Liquid Chromatography(HPLC).The contents are GA 5.792 mg/g,HBA 1.545 mg/g,HA 1.318 mg/g.hypoglycemic activity of the exopolysaccharide from Submerged Culture of G.frondosa by Addition of R.gastrodiae extract and its Main Components.The order of the ?-glucosidase IC50 values is REPS<HEPS<GEPS<HAEPS<CEPS,Among them,REPS had the lowest IC50 value 26.07 mg/mL,which was significantly different from CEPS group(p<0.01).And followed by HEPS,29.95 mg/mL,there was a significant difference from CEPS group(p < 0.05).It can be seen that the addition of the R.gastrodiae extracts and the main components to participate in the deep fermentation of G.frondosa can enhance the inhibition ability of the exopolysaccharide on ?-glucosidase,and HBA is the most significant component among the main components of the R.gastrodiae extract.(3)On Alloxan-induced diabetic mice were used to test the hypoglycemic activity of exopolysaccharide from submerged culture of G.frondosa by addition of R.gastrodiae extract.The results showed that the continuous administration of exopolysaccharides of G.frondosa for 28 days could improve the mental state of diabetic mice to a certain extent,and alleviate the symptoms of polyphagia,polydipsia,polyuria and weight loss in mice.In addition,the three groups of G.frondosa exopolysaccharides significantly reduced the fasting blood glucose level of the model mice,and the hypoglycemic effect of REPS was significantly greater than that of CEPS(p<0.05).The results suggest that the ethanol extract of submerged culture of G.frondosa by addition of R.gastrodiae extract to increase the blood glucose level of its exopolysaccharide.(4)The study on the influence of exopolysaccharide of G.frondosa on glucolipid metabolism,antioxidant enzyme activities and improvement of the degree of organ damage in diabetic mice was carried out to clarify its effects of diabetes complications.The results suggest that three groups of G.frondosa exopolysaccharides could suppress enlargement of liver and kidney,and antagonize atrophy of thymus and spleen.And the three groups had significant effects against the increase of LDL-c,AST and ALT(p<0.05).Furthermore,REPS had significant effects against the reduction of HDL-c,TG and SOD(p<0.05).It indicate that the exopolysaccharide from submerged culture of G.frondosa by addition of R.gastrodiae extract could improve the lipid metabolism,alleviate damage to organs in ALX-induced diabetic mice and enhance the activities of antioxidant enzyme,and inhibit the over production of free radicals.