Glucose oxidase/catalase

Glucose Glucose oxidase Catalase (increases stability of immobilized glucose oxidase) Benzoquinone (electron acceptor)... 

Since the principal constituents of milk are proteins, lipids and lactose, proteinases, lipases and / -galactosidase (lactase) are the principal exogenous enzymes used in dairy technology. Apart from these, there are, at present, only minor applications for glucose oxidase, catalase, superoxide dismutase and lysozyme. Lactoperoxidase, xanthine oxidase and sulphydryl oxidase might also be included, although at present the indigenous form of these enzymes is exploited. 

The protein content of honey is usually around 0.2% (Anklam, 1998 Iurlina and Fritz, 2005). A small portion of this fraction consists of enzymes, notably invertase, diastase, amylase, glucose oxidase, catalase (Anklam, 1998), a-glucosidase, and p-glucosidase (Won et al., 2008). Some are derived from bees, whereas others come from the nectar. Enzyme activity varies among honey samples since the amount of bee saliva, the source of bee enzymes, found in honey varies with the conditions of honey production (Anklam, 1998). 

Co-immobilized Glucose oxidase-Catalase Covalent bond to CPG... 

Experience shows that flow microcalorimetry is a universal technique that is suitable for the investigation of the catalytic properties of immobilized biocatalysts. This review has summarized all basic examples of its application, but has not exhausted all of their potential possibilities. As an example, the steady-state measurement of a bi-substrate enzyme reaction with a co-immobilized glucose oxidase-catalase system was reported [26]. However, there is no report on the evaluation of kinetic properties of partial enzymes in co-immobilized systems. Even the measurement of the overall heat produced in such systems does not provide direct information about partial reactions. We believe that new approaches to analyze these systems based on mathematical modeling can be developed. 

Figure 20.6 Calibration curve for glucose obtained with a miniaturized enzyme thermistor containing glucose oxidase/catalase on superporous agarose using 20 n samples injected in a flow of 100 /zl min. ...

Figure 20.7 The effect of sample volume on the linear range of a thermometric glucose sensor with a 0.6 mm x 10 mm CPG column with glucose oxidase/catalase. The flow rate was 50 /xl min . ... 

Fig.4. Simultaneous measurements of oxygen evolution and 295 nm absorbance changes in BBY membranes upon flash illumination at 2 Hz. Note that the absorbance traces are 5 times shorter than the oxygen traces, to allow at least partial resolution of the ms transient. No electron acceptor was added. Samples were made anaerobic before measurement (glucose, glucose oxidase, catalase).

Hgure 4 Calibration graph for a calorimetric device of the type shown in Figure 3 with a glucose oxidase/catalase column. The sample volume was 20 il. Open squares are for aqueous glucose standards and closed squares are for 10-fold diluted blood samples spiked with glucose. 

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