Exctraction,Purification And Bioactivity Study Of Polysaccharides From Auricularia Auricular

Auricularia auricular belongs to the edible fungi;and it is functional food that has a long history in China and even the world.Meanwhile,Auricularia polysaccharide is one of the main active ingredients of Auricularia auricular.Although there are many studies on the functional activities of fungal polysaccharides over the world,there are few systematic studies on the polysaccharides of Auricularia auricular.In this research,the Auricularia auricular from Yabian was used as the research object.The response surface methodology was used to optimize the high-temperature steam extraction process.The final extraction conditions were determined as follows:extraction solid-liquid ratio 1:50(g/mL),extraction temperature 120℃,extraction time 85 min.The extraction yield of polysaccharides was(48.38±1.64)%.Compared with the traditional hot-water extraction method,the yield of polysaccharides was increased by about 4 times,indicating that high-temperature steam extraction method can efficiently obtain polysaccharides from Auricularia auricular.Subsequently,the physicochemical properties and functional activities of Auricularia auricular polysaccharide were analyzed in this study.The results showed that the average molecular weight of polysaccharide was 6.65 ×105 Da,the uronic acid content was 0.23 g/g,and sulfate was not detected.The monosaccharide components include mannose,glucose,galactose,rhamnose,glucuronic acid,galacturonic acid,xylose,and fucose,but arabinose is not detected.At the same time,Auricularia auricular polysaccharide showed good antioxidant capacity,among which the IC50 to superoxide ion,ABTS+-and DPPH·scavenging effect were 0.65 mg/mL,0.78 mg/mL and 1.47 mg/mL,respectively;and,it had good reducing power.However,the highest clearance rate of hydroxyl radicals.On the other hand,the Congo red experiment showed three-stranded helix structure in Auricularia auricular.While non-enzymatic glycosylation experiments also showed that it had a certain inhibitory effect on the formation of dicarbonyl compounds during glycosylation.In conclusion,not only does it reflect that the activity of polysaccharide is well preserved,but also Auricularia polysaccharide showed great potential for application in anti-oxidation and anti-aging.In vitro anti-lung cancer activity experiments.Auricularia auricular polysaccharide could effectively inhibit the growth and proliferation of non-small lung cancer cells A549,and the best effect at a concentration of 0.4 mg/mL.Polysaccharide could also promote the apoptosis of lung cancer cells through the endogenous apoptosis pathway.By destroying the mitochondrial integrity,the mitochondrial depolarization led to inhibition of the S-phase of the cell cycle,so the proliferation of cells was blocked;at the same time,it is promoted by the p53/Akt/JNK pathway.Apoptosis of lung cancer cells eventually leads to cell death.This subject achieves efficient extraction of active polysaccharide,and at the same time,it has proved that it has good anti-oxidation and anti-tumor activity in vitro.This provides a good theoretical basis and experimental basis for the future research,development and application of Auricularia auricular polysaccharide.