1.5-gluconolactone

Table 6 Hsts the leavening acids and the corresponding rates of reaction. The leavening acids most frequently used iaclude potassium acid tartrate, sodium aluminum sulfate, 5-gluconolactone, and ortho- and pyrophosphates. The phosphates iaclude calcium phosphate [7758-23-8] CaHPO, sodium aluminum phosphate, and sodium acid pyrophosphate (66).

Another example is the absence of oxygen exchange with solvent in the hydrolysis of gluconolactone. Simple acyclic esters usually undergo isotopic exchange at a rate that is conqietitive with hydrolysis. This occurs through the tetrahedral addition intermediate. 

Gluconolactone shows no exchange. The reason is that the tetrahedral intermediate is formed and breaks down stereoselectively. Even though proton exchange can occur in the tetrahedral intermediate, the anomeric effect leads to preferential loss of the axial oxygen. 

Enzymes are proteins of high molecular weight and possess exceptionally high catalytic properties. These are important to plant and animal life processes. An enzyme, E, is a protein or protein-like substance with catalytic properties. A substrate, S, is the substance that is chemically transformed at an accelerated rate because of the action of the enzyme on it. Most enzymes are normally named in terms of the reactions they catalyze. In practice, a suffice -ase is added to the substrate on which die enzyme acts. Eor example, die enzyme dial catalyzes die decomposition of urea is urease, the enzyme dial acts on uric acid is uricase, and die enzyme present in die micro-organism dial converts glucose to gluconolactone is glucose oxidase. The diree major types of enzyme reaction are ... 

Table 11-2 gives the results of the computer simulation and Ligure 11-17 shows the concentration profiles of the cell, gluconolactone, gluconic acid, and glucose with time. These profiles are in good agreement with the experimental data of Rai and Constantinides [14]. 

Concentration of the cell, gluconolactone, gluconic acid, and glucose with time using the Runge-Kutta-Gill method... 

Figure 11-17. Concentration profiles of cell, glucose, gluconolactone, and gluconic acid with time.

The ability of bacteria - particularly Pseudomonas spp. and Glucottobader spp. - to produce gluconolactone and gluconic acid has been exploited and the process is used commerdally, mainly in the production of the lactone. 

Finally gluconolactone - largely produced from Gluconobacter suboxydans is used in baking powder and bread mixes and other areas where its effervescent properties may be exploited. 

Conversion of the gluconolactone to gluconic add occurs under certain conditions by spontaneous hydrolysis, though a rather specific lactonising enzyme is present in cells. 

Production of D-gluconolactone from glucose in several fungi is a one-step process catalysed by glucose oxidase. 

False. D-gluconolactone is produced directly from glucose via glucose oxidase. 6-phosphogluconolactone is an intermediate in the hexose monophosphate pathway. 

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