Cellulose Thermal Kinetics Of Enzymatic Degradation Of Cellulose

With the development of society and the increase of population, the food problem causes the people's concern increasingly. Only depending on the limited farmland will hardly satisfy the demand of the increasing population. At the same time the economic development makes the depletion of the energy increase quickly. So the energy crisis and pollution of the environment have become an important problem that mankind face. To solve these problems, the exploitation of the cellulose resources causes more concern and attention of the international community. In our country there are rich cellulose resources. Hydrolyzing these wastes to produce glucose using enzyme is equal to raising the food yield by 100 percent under the premise that the farmland area is not increased. The glucose is the important raw material of many chemical materials such as ethanol and methanol and so on. In addition, hydrolyzing these wastes using enzyme can also prevent pollution. Seeing from these aspects, dealing with the wastes like crop stalks using enzyme can be said to get three results with one action and have the signality. Therefore it get the concern of many scientists and have wide foreground.The studies in this paper provide theoretical basis for the degradation of the crop stalks by cellulase. A series of experiments on cellulose degradation by cellulase were finished with the 2277-Thermal Activity Monitor and 8-Channel Microcalorimeter(TAM Air). The power-time curves determined were analyzed by thermokinetic theory and reduced extent method , and then the related conclusions were drawn.. The main contents are as follows: 1. the study on the optimal conditions under which the cellulose was degraded by cellulaseThe power-time curves of cellulose degradation by cellulase at different acidity and different temperature were determined by microcalorimetry. Using thermokinetic theory and reduced extent method, the Michaelis constant(K_m) andthe maximum velocity(Vmax) of the reaction were obtained. The relationship between the maximum velocity and the acidity and temperature were established and the optimal acidity (pH=4.60) and optimal temperature (338K) of cellulose degradation by cellulase were got.2. the study on the inhibition and activation of metal irons to cellulaseThe power-time curves of cellulose degradation by cellulase without metal irons and with the existence of metal irons of the same and different concentrations were determined by microcalorimetry. Using thermokinetic theory and reduced extent method, the Michaelis constant(Km), apparent Michaelis constant(Km), maximum velocity(Vmax) and the apparent maximum velocity(Vmax) of the reaction were obtained. By comparing, the differences of inhibition or activation of different metal irons of the same concentration to cellulose degradation by cellulase and of the same metal iron of different concentrations were seen. Therefore the active metal iron (Cu2+) to cellulase and the changing tendency along with the concentrations of the effect (The activation increases when concentration increases from 0 to 20 mmol/L) were obtained.3. production analysisThe qualitative and quantitative analysis of the production of cellulose degradation by cellulase were done by Fehling reaction, thin layer chromatography and DNS method. By calculating the productivity(21.6%) of cellulose degradation by cellulase was obtained.4. the study on the optimal solvent of celluloseThe power-time curves of the degradation of solutions in which cellulose was solved by different solvents by microcalorimetry. By comparing the heat produced in the reactions (the area under the curve), the solvency of different solvents could be seen. So the optimal solvent (NMMO system) of cellulose was chosen.the innovation of this paper: 1. The methods of determining enzyme activity, weight reducing, saccharifying...