| Cellulose is the most abundant organic substance on the earth,and is the most widely origins.It has already been a type of re-growed significant resources and energy.The special structure of the cellulose molecular and the particularity of the existance state of cellulose material in nature make this precious resources to make good use of unrationally.The results of many studies showed that the degradation and utility of cellulose by biotechnology has its unique advantages.In order to degrade and transform the cellulose to small moleculars or other nutrient mateirals,the key problem is to screen and separate the preponderant strains.In this thesis,by using cellulose congo-red culture medium and filter paper culture medium,we got the preliminary screening results;by using the rate of cellulose-enzyme reaction,we got the final screening results.By such repeating screening,we got a strain of fungi which had a good ability to degrade cellul-ose from the samples which were from the spots where the waste cellulose ha-d been placed for many years.It was classified as Eupenicillium javanicum by the analysis of it's morphology and 18S rRNA gene sequences.In our experiment,We studied various factors affecting Eupenicillium javanicum ZN-205 liquid-state fermetation,which were culture conditions and substrate components in our experiment condition.The best carbon source was the stalk powder,and the best nitrogen source was KNO3,added some bran into the substrate can improve enzyme activity obviously, and the addition of surfactants did not have obvious infection on the cellulose activity. Using the quadrature experiment we got the most suitable ferment condition:loaded 100mL liquid fermente substrate into 250mL triangular flask,the initial substrate pH was 5.5,the concentration of KN03 was 1.0%, the ratio of stalk powder and bran was 7:3,added 0.4% tween-80 to the substrate,and than fermented for 5d at 30℃.Under this condition the microorganism had the highest enzyme production,the enzyme activity of CMCase is 24.52IU/mL, and the FPA is 2.68IU/mL.In this paper,we studied the extracting condition of cell-external enzyme and the enzyme-actuating reaction condition.The results showed that used the rotate speed of 3000r/min and centrifuge time of 15min to extract the enzyme when mensurate the enzyme-actuating reaction of CMCase,the study results showed the optimal condition of CMC-enzyme was at pH 5.0,60℃when react time was 30min and the concentration of substrate was 2.0%;and that used the rotate speed of 4000r/min and centrifuge time of 10min to extract the enzyme when mensurate the enzyme-actuating reaction of filter paper enzyme,the study results showed the optimal zymohydrolysis condition of filter paper enzyme was at pH5.0,50℃when react time was 60min and used 1×4cm2 filter paper as the substrate.By studing on the stability of cellulase,we concluded that the CMC enzyme had good stability when the temperature was between 40℃and 60℃,and when temperature was under 40℃or above 60℃,the enzyme activity descended rapidly; and the enzyme also had good stability when the pH was between 4 and 5,and enzyme activity declined quickly when pH below 3 or above 6.The filter paper enzyme had good stability when the temperature was at 40℃and 50℃,and the pH range among which enzyme had good stability was 5 and 6.The effects of mental ions to the enzyme-actuating reaction were obvious,when the concentration was 1.0mmol/L, Na+,K+,Fe2+,Mg2+ improved cellulase activity,and Zn2+,Cu2+,Ca2+,Mn2+ were prohibitive for the cellulase activity.
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