| Grifola frondosa is a rare edible fungus,which has good value in food and medicinal value.The separation,extraction and antibacterial research of Grifola frondosa polyphenols and polysaccharides was researched which obtained from submerged fermentation mycelium.Submerged fermentation medium for Grifola frondosa was optimized by methods of single factor and response surface analysis,the best medium was glucose 18.02g/L,and bran 5.32g/L,VB6 37.04mg/L,KH2PO4 2.00g/L,MgSO4 3.00g/L,pH natural.Optimal condition was verified multiple times,mycelium dry weight was 6.06g/L,which close to the predicted value(5.86g/L).Mycelium cultivated in this media was freeze-dried into powder.Polyphenols were extracted from the powder with 75%ethanol,absorbed by Macroporous Resin AB-8.Sample concentration of polyphenols was 0.20mg/ml,injection volume was 1.00ml/min,elution buffer was 80%ethanol,elution speed was 0.50ml/min,liquid volume was 10.00ml per tube,peak value of the polyphenol content was 49.00μg/ml.Alkaline polysaccharides of Grifola frondosa were extracted from the mycelium residues after polyphenols extraction,the optimum extraction conditions was obtained by response surface analysis method,which was NaOH 0.29mol/L,ratio of liquid to solid 66.16:1,extraction time 32.7min.Extraction rate of alkaline polysaccharides were 0.73%after three parallel experiments,theoretical value was 0.70%,the deviation between theoretical value and measured value was small.Alkaline polysaccharides of Grifola frondosa chromatographied by DEAE-52 anion exchange column,and got three elution peaks.Three elution peaks were separated and purified by Sephadex G-200 gel column,and three elution peaks was obtained and named Ⅰ-1,Ⅱ-1,Ⅲ-1.Purified polyphenols and polysaccharide Ⅱ-1 with high sugar content from Grifola frondosa were used in vitro antibacterial test by the filter paper method.There is no significant inhibitory effects of Grifola frondosa polyphenols on Aspergillus niger,Aspergillus oryzae,Penicillium,there were no obvious zone of inhibition,antibacterial effects on bacteria and yeast were good.Antibacterial effect of Grifola frondosa polyphenols would be no activity when the temperature higher than 80℃ polysaccharide Ⅱ-1 with high sugar content was used in vitro antibacterial experiment,but there is no obvious zone of inhibition. |
