| In this thesis, we first studied ligninolytic enzymes production by Phanerochaete chrysosporium immobilized on porous polyurethane foams. On the basis of this, we studied crude separation and purification of the ligninolytic enzymes, immobilization of the ligninolytic enzymes and the degradation of dyes by the immobilized ligninolytic enzyme.From our investigation, we found that the effect of ligninolytic enzymes production by Phanerochaete chrysosporium immobilized on porous polyurethane foams was good. Among the seven kinds of polyurethane foams tested, the first is the most effective one in fermentation experiment. The mycelium immobilized stablely in the foam and the following fermentation liquor was clear. It is beneficial to the post-treatment if the liquor is clear. The polyurethane foam is a suitable carrier for its cheap price and effectiveness.We optimize three parameters that are the most effective in the ligninolytic enzymes production through orthogonal method: the amount of carrier, the amount of glucose and the rate of rotation. The optimal values of the three parameters are 1.03g/100mL, 6g/L and 190r/min. The production was increased in the optimal parameters and the activities of the lignin peroxidase, manganese peroxidase and glyoxal oxidase are 90U/L ^ 3.52U/mL and 27U/mL respectively. Additionally, inoculation amount test showed that this parameter influence little in fermentation.Repeated batch fermentation of immobilized Phanerochaete chrysosporium indicated that we can get the ligninolytic enzyme quicker but lower in activity if we prefer adding initial fermentation medium to adding medium which is low in glucose or even no glucose. We can reuse the immobilized mycelium and bypass the incubation period after immobilization. Furthermore, reducing glucose is an economic way in reducing production cost.We did some crude separation and purification of the ligninolytic enzymes. The activities of the three kinds of enzymes increased to 1.5 times, 2.18 times and 2.78 times of their initial activities, The acquirement rate of their activities were 30.7%> 43.6% and 55.6%. The characteristics of the enzymes such as the optimal pHs, theoptimal temperatures and the stabilities of the enzymes in different pH and different temperatures meet well with what the previous literatures had said.The immobilization of the ligninolytic enzymes showed that sodium alginate is a good carrier. It is not only convenient in manufacture but also economic in cost. After immobilization, the spectrums of the optimal pH and optimal temperature were expanded.When the six kinds of dyes were degraded directively by the enzyme solution, they all had different extents of degradation except disperse Yellow RGRL, although the amounts of degradation were not high. We also found that acetic acid buffer was the best of the three kinds of buffers tested in their influence on the stability of sodium alginate pellet. In the test of using immobilized ligninolytic enzymes on sodium alginate to degrade the five kinds of dyes, four kinds of dyes could be degraded effectively except D/RS Brown. The decolorization rate of disperse Rubine could reach over 90%. In comparison of the decolorization results of the three concentrations of the dyes we tested, we could conclude that the decolorization rates and extents of the higher concentration are higher than those of the lower concentration. This difference is due to the fact that the dye concentration grad between the outside and inside of the sodium alginate pellet is higher when the dye concentration of the outside is higher. The high grad is of great benefits to the diffusion of dye molecule into the pellet and to attach the enzymes. Moreover, the differences among the molecules of different dyes are also contributed to the different decolorization rates. The bigger the molecule, the more difficult the entering of them into the pellets.We investigated the existence of glyoxal oxidase in the immobilized ligninolytic enzymes. Formaldehyde was added into the degradation...
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