To compare the properties of free enzyme with the immobilized enzyme the optimum pHs have changed from 4.0 to 4.0-4.4, the optimal temperatures from 50 to 50-55℃ and Km values from 0.16% to 0.28% of starch solution.
The Michaelis-Menton constant of the immobilized enzymes and native enzyme are measured. The values are: Km＝97.78mmol/L(native enzyme),Km(app)=18.01mmol/L(CO32-LDHs-IE),Km(app)=5.36mmol/L(GLU-LDHs-IE)。
The stabilities of different immobilized enzymes and free HRP were also compared,and the stability of immobilized HRP with Fe_3O_4-gelatin as carrier was considerably higher than the stabilities of other enzymes.
Using immobilization enzyme acidification phase and UASB to produce methane phase as two-phase anaerobic fermentation process,the change characteristics and the change rate of organic acid and ethanol organic,composition and fermentation type as well as COD removal were studied.
The optimum immobilization conditions of enzyme were as follows: enzyme load was 15mg/g carrier, pH was 6.5.The pH and temperature optima were 6.5 and 70 C for immobilization enzyme. All above indicate this kind of particle can be a good enzyme immobilization carrier. The reverse phase suspension and embedment technique were adopted to prepare magnetic agar microsphere.
The chitosen menbrance with degree of deacetylation of 86.44% and with a melocular weight of 1.288×106 Datlon is used as support for enzyme immobilization. The optimum conditions for immobilizing glucose oxidase on glutaradehyde-pretreated chitosan membrane is 0.025% glutaradehyde pH6.5 12hours and 0.2mg/ml of the enzyme concentration at the room temperature.
The chitosan with degree of deacetylation of 92.84%, and with weight of 7.84105 dalton is used as carrier for enzyme immobilization. The optimum conditions of immobilization are pH6.0 and 3% glutaradehyde. Recovery of enzyme activity is 59%.
Now with the research development in field of biomedicine and bioengineering, people are exploring various functional polymer microspheres which can serve as smart or intelligent tools for drug delivery, biomacromolecules purification, biosensor and enzyme immobilization,etc.
The catalytic constant (25 s-1) andKM (0.17 mM) for the immobilized enzyme for the hydrolysis of N-acetyl-L-tyrosine ethyl ester are comparable to the corresponding characteristics for the free enzyme.
Thermal inactivation of the immobilized enzyme under the reaction conditions was studied.
The kinetics of acidic inactivation of the native and immobilized enzyme was studied.
The immobilized enzyme was more resistant to temperature and pH.
Methods for stabilization of the immobilized enzyme were developed, and some kinetic parameters of the immobilized preparations were determined.
Emphasis will be placed on recent biological and biomedical developments and trends such as enzyme immobilization, cell isolation, protein purification, target drugs and DNA separation.
The advantages and disadvantages of each of the above polymers for enzyme immobilization are discussed.
In the other, a certain type of enzyme immobilization on the support is required.
Two kinds of disperse carbonaceous materials-activated carbon NORIT and carbon black PM-100, were used as matrices for enzyme immobilization.
The pH of the solution affected the adsorption capacities of the selected immobilization matrices; larger amounts of CAT adsorbed were estimated in neutral and alkaline solutions than under acidic conditions for enzyme immobilization.