| In this essay,Hericium mycelium was employed as the raw material.The extraction,separation,purification of Hericium erinaceus polysaccharide were systematically studied and the purity was tested.In industrial production,the manufacture of Hericium erinaceus polysaccharide was confronted with problems as polluting environment,wasting resources,high labor intensity,unstable quality,high production costs and low economic efficiency.Considering the perspective of the application of Hericium erinaceus polysaccharide and its current situation in research area,this dissertation established a modern technique of extraction,separation and purification in the principal of making full use of resources,improving the extraction yield and its economic efficiency,in the hope of realizing efficient,continuous,low cost and high quality manufacture in mass production.The main research contents and conclusions are as follows:1.Extraction process of Hericium erinaceus mycelium polysaccharideThe hydrolytic efficiency of various enzymes were observed.The enzymolysis technology and ultrasonic extraction were combined and compared with each other and optimized by single factor test,orthogonal test and response surface test.The results showed that when edible fungus hydrolase A01 enzyme was combined with A02,the polysaccharide extraction efficiency became the highest,which was up to 5.86%.The optimum condition of polysaccharide extraction by edible fungus hydrolase was established through single factor experiment and orthogonal experiment.The optimal conditions of enzymatic hydrolysis were:edible fungus hydrolase A01 dosage 0.7%,enzymolysis time 3 h,pH 4.5,A02 dosage 0.5%,enzymolysis time 4.5 h,pH 7.0,enzymolysis temperature 55 ?.The polysaccharide extraction yield was 6.97%under the condion.The optimum ultrasonic condition of polysaccharide extraction was established by single factor test and response surface test.The best ultrasonic conditions were:ultrasonic temperature 40?,ultrasonic power 700 W,ultrasonic time 30 min,ultrasonic frequency 20KHz,solid-liquid ratio 1:30(w/v).The theoretical value of polysaccharide extraction yield was 6.7696%.Based on the optimum conditions of the enzymatic and ultrasonic extraction,the two methods were combined.The process was to use edible fungus hydrolase treatment before ultrasonic extraction.The extraction yield of polysaccharide was 10.96%.It was significantly higher than other methods under the optimal conditions.2.Separation and purification process of Hericium erinaceus mycelium polysaccharideThe glucose value(DE value)was used as the index to characterize the level of starch hydrolysis.Orthogonal test method was used to optimize the enzymatic conditions for starch removal and the deproteinization was studied;further separation and purification of polysaccharide by DEAE-52 cellulose ion-exchange column chromatography were also investigated.The results showed that the thermostable alpha amylase hydrolysis optimal conditions were enzyme dosage of 0.8 mg/g,at pH6.5,100? for 40 min;the optimum conditions for glucoamylase hydrolysis were enzyme dosage of 30 mg/g,at pH4.5,6?,for 2 h.The DE value was 96.07%and the polysaccharide purity reached 70.31%when using glucoamylase after thermostable alpha amylase enzymolysis.Protein was removed by using trypsin and Sevage method,the deproteinization conditions were at pH8.0,37? for 30 min.The protein removal rate can reach 93%when trypsin at a dosage of 100 U/mL and sevage reagent at a volume of 1:1 which had the best purification effect DEAE-52 column chromatography was applyed to obtained polysaccharide HPS-1 and HPS-2,which was 15.02%and 76.83%respectively.The recovery rate of polysaccharide was 91.58%.UV spectral analysis indicated both HPS-1 and HPS-2 contained no nucleic acid or protein. |
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