Extraction Optimization And Anti-diabetic Activities Of Polysaccharides From Phylloporia Ribis(Schumach:Fr.) Ryvarden

P.ribis is a kind of fungi that isparasitic on the root of Lonicera japonica.It has good effects of anti-inflammatory,detoxification,analgesic and immune regulation effects.The fruiting bodies of P.ribis contain polysaccharides,triterpenes,sterols and other active components.It is mainly used for the treatment of diabetes,cancer and ulcers.P.ribis is a new resource food.At present,there are few studies on P.ribis.Studies have shown that fungal polysaccharides have biological activities such as lowering blood sugar and regulating immunity.The P.ribis polysaccharides have potential hypoglycemic and anti-diabetic effects as a natural fungal polysaccharide.In this paper,the P.ribis polysaccharides were extracted by water extraction and alcohol precipitation,decolorization by activated carbon adsorption.The extraction process was optimized by signle factor experiment and response surface methodology.The results showed that the extraction time and ultrasonic power had great influence on the P.ribis extraction rate.The activated carbon content and extraction temperature had the great influence on the P.ribis decolorization rate.Finally,the optimum extraction conditions were solid-liquid ratio 1:10,extraction time 120 min,ultrasonic power 406W,and the extraction rate was 3.89%.The optimum decolorization conditions was as follows:the content of activated carbon was 4.7%,the decolorization temperature was50℃,the decolorization time was 55 min,and the decolorization rate was 86.37%.It provides reliable technological conditions for the extraction of P.ribis Polysaccharides,and provides materials for studying the anti-diabetic effect of P.ribis Polysaccharides.The molecular weight distribution of P.ribis Polysaccharides was determined by HPLC.The molecular weight distribution of P.ribis Polysaccharides was determined by gel chromatography.The antioxidant capacity of the P.ribis Polysaccharides determined by DPPH-ethanol method,ABTS-persulfate method,ferrous sulfate salicylic acid method and Fe³⁺reduction power by potassium ferricyanide method.In order to explored the anti-diabetic effect of P.ribis Polysaccharides,we established astreptozotocin induced diabetic rat model,and studied the effects of P.ribis Polysaccharides on the physiological and biochemical changes,liver morphology and cytokine expression in rats.Based on the results of high-throughput 16S r RNA sequencing,the microbial flora distribution in rat intestinal contents was analyzed.The results showed that P.ribis Polysaccharides could significantly reduce fasting blood glucose in diabetic rats,significantly regulate triglyceride,total cholesterol,high and low density lipoprotein levels,inhibit serum alanine aminotransferase and aspartate aminotransferase activity,and improve liver damage induced by diabetes,and significantly reduce NF-in liver.κB、TNF-α、IFN-γ、MCP-1 level.It is speculated that P.ribis Polysaccharides can regulate the lipid metabolism in diabetic rats by repairing the liver injury caused by diabetes.At the same time,increasing the relative abundance of Proteobacteria,Prevotella and Allobaculum,the relative abundance of Bifidobacterium,Escherichia-Shigella,Turicibacter and Clostridium-sensu-stricto were decreased,the abundance of intestinal microbes in rats was adjusted,and the distribution of intestinal microflora in diabetic rats was improved.