Study On Extraction,Antioxidant Activity And Probiotics Activity Of Polysaccharide From Mycelia Of Lepista Sordida

This subject mainly uses microwave and ultrasonic to synergize the extraction of Lepista Sordida polysaccharides（LSP）.The extraction conditions are optimized by exploring the stability of extraction conditions,single factor experiments,and orthogonal experiments,and the crude extraction of Lepista Sordida mycelium The liquid is purified by graded alcohol precipitation to obtain three components:40%-LSP-UMSE,60%-LSP-UMSE,80%-LSP-UMSE,explore 40%-LSP-UMSE,60%-LSP-UMSE,80%-LSP-UMSE’s physical and chemical composition,antioxidant activity,and beneficial life.The specific research content and results are as follows.1.Optimizing the conditions of microwave and ultrasonic collaborative extractionThe extraction of LSP was carried out through single-factor screening experiment,and the factors that had obvious influence on the extraction rate were obtained.Three-factor three-level orthogonal experiment was carried out.Finally,the best extraction conditions for microwave and ultrasonic collaborative extraction were extraction 2 min,material-liquid ratio 1:20g/m L,microwave power 100 W,ultrasonic power 100 W,the total sugar extraction rate was 13.75%,and the relative standard deviation was 1.27%.2.Antioxidant activity researchThe in vitro antioxidant activity of polysaccharides extracted by microwave and ultrasonic was measured,and the graded alcohol precipitation polysaccharides extracted by hydrothermal extraction were used as comparison.The results of maximum clearance rate,maximum clearance rate concentration,and half clearance rate concentration showed:40%-LSP-UMSE,80%-LSP-UMSE component is significantly better than the hydrothermally extracted graded alcohol-precipitated polysaccharides,and the oxidation resistance of 60%-LSP-UMSE compared to 60%-LSP-HWE is not obvious.In terms of overall anti-oxidation,the polysaccharide extracted by microwave and ultrasonic is better than the polysaccharide extracted by hydrothermal.3.The physical and chemical properties of Lepista Sordida polysaccharidesThe three components of 40%-LSP-UMSE,60%-LSP-UMSE,and 80%-LSP-UMSE all have sugar characteristic absorption peaks at UV 200 nm,while 40%-LSP-UMSE and 60%-LSP-UMSE The two components also have weak absorption peaks at wavelengths of 260 and 280 nm,that is,they contain trace amounts of nucleic acids and trace proteins.FTIR analysis showed that 40%-LSP-UMSE,60%-LSP-UMSE,and 80%-LSP-UMSE all haveβ-glycosidic bond configuration,and all three components may all have pyranoside ring configuration;The main monosaccharide components of 40%-LSP-UMSE are Glucose（183.88 mg/g）,Mannose（22.93 mg/g）,Galactose（2.59 mg/g）,Ribose（2.10 mg/g）,Glucuronic acid（1.63mg/g）;The main monosaccharide components of 60%-LSP-UMSE are Glucose（41.22 mg/g）,Mannose（120.40 mg/g）,Galactose（7.27 mg/g）,Ribose（8.21 mg/g）,Glucuronic acid（2.68mg/g）,L-fucose（2.33 mg/g）;The main monosaccharide components of 80%-LSP-UMSE are Glucose（30.87 mg/g）,Mannose（11.79 mg/g）g),Galactose（4.59 mg/g）,Ribose（2.09 mg/g）,L-fucose（1.23 mg/g）;4.The effect of LSP-UMSE on the growth and proliferation of Lactobacillus caseiThe graded alcohol-sedimentation polysaccharides of Lepista Sordida can promote the proliferation of Lactobacillus casei to a certain extent.Glucose was used as a negative control,and inulin was used as a positive control.The results of 72h growth curve and 24h acidity bar graph of three LSP-UMSE pure carbon sources showed 40%-LSP-UMSE,60%-LSP-UMSE,80%-LSP-UMSE components are significantly better than inulin;in the experiment to verify whether the polysaccharides can stimulate the growth of Lactobacillus casei,three LSP-UMSEs were compounded at 0.5%with a monosaccharide-polysaccharide ratio of 9:1Polysaccharide MRS did not show the growth-promoting activity.40%-LSP-UMSE has a better probiotic effect than inulin in slowing down decay and increasing final OD₆₀₀and increasing acid production.40%-LSP-UMSE,80%-LSP-UMSE has a better acid-producing probiotic effect than inulin in the verification of carbon source;the study on bile salt tolerance activity found that the three kinds of LSP-UMSE used as carbon source to cultivate Lactobacillus casei significantly improved its tolerance to glucose.Bile salt activity.