| Agaricus blazei Murill, called Brazil Mushroom commonly, is a kind of edible and medicinal mushroom. It is getting research hotspot recently for its distinctive nutrient and medicinal values on tumor and immunity.The polysacchande from Agaricus blazei Murill bodies was extracted and purified, and the physicochemical properties of which were determined. It was reported that the polysaccharides from Agaricus blazei Murill mycelia is effective against tumor. Moreover, the liquid-culture of mycelia will make production of polysaccharides industrialization more easily, so the liquid culture conditions of Agaricus blazei Murill mycelia were studied as well. The results and creative points are mainly as follow:The polysaccharides from the fruiting bodies of Agaricus blazei Murill were extracted with hot water(100 ),oxalic acid (4 ),sodium hydroxide solution and compound enzyme respectively. Contrasting the effects of these methods on the extracting rate of the polysaccharides, the result showed compound enzyme method was a kind of better method and its optimum parameters were obtained. With the temperature of 45 ,pH of 70,and extract time of 3 hours ,the higher extracting rate of polysaccharides was reached.Four schemes were used to remove protein from the extracted polysacchande and the results revealed that the scheme of enzyme and trichloroaceticacid -n-butanol were better than others. Combining these two schemes to remove protein, when the polysaccharides were enzymic hydrolysis for an hour in 40 癈 solution of pH 5.0, added trichloroaceticacid-n-butanol twice as much as polysacchande solution, stirred for 20 minutes, and put quietly for one and a half hour, the higher removal rate of protein was obtained.Adopting active carbon, diatomite and hydrogen peroxide solution to decolourize the extracted polysacchande, it was found that the color of polysaccharide solution did not change with diatomite, the decolour effect of hydrogen peroxide solution was better than that of active carbon. The absorbance of polysaccharide by active carbon cause the polysaccharide content dropped. For hydrogen peroxide solution, there is no such phenomenon. So hydrogen peroxide solution is an ideal decolourant. When the hydrogen peroxide solution of two times as much as polysaccharide solution was added, the effect of decolour is the better, and the transmissivity of solution is 93.5%.After treated with protein-removal and decoloure, the purified polysaccharide was obtained by further colume chromatography of DEAE-Sephadex A-25 and Sephadex G-200.The purified polysaccharide (ABM) is prone to dissolving in polar solvent and difficult to dissolve in non-polar solvent ,and its homogeneity was verified by gel filtration, paper andthe electrophoresis of acetic acid fiber membrane . The components of ABM were identified by paper chromatography and UV and IR spectrum , and it was composed of D-Glc, D-Gal, nucleic acid, and a little protein.The result of liquid culture of Agaricus blazei Murill showed that the optimum carbon source and nitrogen source were sucrose, wheat flour and beef creanK peptone respectively, the range of pH was from 5 to 7 and the spawn rate was 10%.Considering the notable effects of ratio between carbon and nitrogen on the mycelia, response surface experiment were designed to analyze the comprehensive utilization of mycelia on carbon and nitrogen. The results revealed that when 3.64% wheat flour and 0.35% beef cream were added into the liquid culture medium, the biomass of mycelia reach the higher level.By orthogonal experiments, the best technique conditions were obtained. The parameter were 10% of spawn rate, 7.0 of pH, 200r/min of rotation speed, and 26 'C of fermentation temperature.The creative points are as following:1 .The methods of removing protein and decolouration from Agaricus blazei Murill polysaccharides have not been reported .By contrasting several schemes, the better methods and parameters were determined in this paper.2.The researches of Agaricus blazei Murill polysa...
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