Glucose solid

Many of the solids around us are ionic. They include most of the minerals that form our landscapes. Many others are molecular, in which electrically neutral molecules stack together under the influence of intermole-cular forces, as in ice and glucose. Solids also include network solids such as diamond and quartz, in which all the atoms in an entire crystalline region are covalently bonded in place. 

Fig. 1. —Action of Proteus 0X2 bacteria on melezitose monohydrate (initial concentration, 5.0%) in system held at pH 5.6 and 23°C. Open circles represent free reducing sugars, calculated as glucose solid circles represent invertase-sensitive material, calculated as sucrose.

Figure 5.16. ACS reagent grade dextrose (glucose) solid inside USP amber vial. Conditions of Figure 5.9, average of five 10 sec integrations. Beam entered through bottom of USP vial, and vial spectrum was subtracted.

Fig. 12. Fermentation of glucose and xylose present in the crude hydrolysate of corn fiber by genetically engineered Saccharomyces yeast strain 1400(pLNH32). The corn fiber hydrolysate was provided by Cargill, Inc. The major sugars present in the hydrolysate are glucose, Xylose, and-arabinose. Symbols solid square glucose solid circle xylose solid triangle ethanol open circle arabinose open triangle xylitol and arabitol open square glycerol...

G = percentage of commercial glucose solids a = direct polarization, normal soln. and S = percentage of cane sugar. 

Express the results in terms of commercial glucose solids polarizing + 21 i°V. (This result may be recalculated in terms of commercial glucose of any Baume reading desired.)... 

Figure 1. Time course of the rumen fermentation. Solid lines show nitrogen in the solids fraction for 5 g/liter glucose (solid circles) and for 5 g/liter sugar beet pulp (open circles). The high initial value for sugar beet pulp represents its protein content as received.

Fig. 14. Time courses for ampicillin squares) a-aminobenzylpenicilloyl glucose solid circles) piperazine-2,5-dione derivative open dries), and a-aminobenzylpenicilloic acid triangles) in the reaction between ampicillin (1.55 x 0 M) and glucose (10% W/V) at pH 9.40 (0.2 M carbonate) and 22 °C. (Bundgaard and Larsen 1979)...

Figure 2(b) Cycfic voltarntnograrn for the poly(edierainme quinone) polyiner (b) / glucose oxidase / carbon paste electrode (scan rate SmV/s) in pH 7.0 phosphate buffer (with O.IM KCl) solution with no glucose present (dashed line) and in the presense of 0. IM glucose (solid line). 

Carry out this preparation precisely as described for the a-compound, but instead of zinc chloride add 2 5 g. of anhydrous powdered sodium acetate (preparation, p. 116) to the acetic anhydride. When this mixture has been heated on the water-bath for 5 minutes, and the greater part of the acetate has dissolved, add the 5 g. of powdered glucose. After heating for I hour, pour into cold water as before. The viscous oil crystallises more readily than that obtained in the preparation of the a-compound. Filter the solid material at the pump, breaking up any lumps as before, wash thoroughly with water and drain. (Yield of crude product, io o-io 5 g.). Recrystallise from rectified spirit until the pure -pentacetylglucose is obtained as colourless crystals, m.p- 130-131° again two recrystallisations are usually sufficient for this purpose. 

Conversion of (3- into a-glucose penta-acetate. Add 0-5 g. of anhydrous zinc chloride rapidly to 25 ml. of acetic anhydride in a 200 ml. round-bottomed flask, attach a reflux condenser, and heat on a boiling water bath for 5-10 minutes to dissolve the solid. Then add 5 g. of the pure P glucose penta-acetate, and heat on a water bath for 30 minutes. Pour the hot solution into 250 ml. of ice water, and stir vigorously in order to induce crystaUisation of the oily drops. Filter the solid at the pump, wash with cold water, and recrystaUise from methylated spirit or from methyl alcohol. Pure a-glucose penta-acetate, m.p. 110-111°, will be obtained. Confirm its identity by a mixed m.p. determination. 

In a 50-100 ml. conical flask place a solution of 0 -5 g. of glucose in 5 ml. of water, 12-15 ml. of 10 per cent, sodium hydroxide solution and 1 ml. of benzoyl chloride, cork tightly, and shake until the odour of benzoyl chloride has disappeared and a crystalline (frequently sticky) soUd has separated. Filter oflF the solid, wash it with a Uttle water, and recrystaUise it from ethyl or n-butyl alcohol. (If the product is sticky, it should be removed, and spread on a porous tile before recrystaUisation.) Glucose pentabenzoate has m.p. 179°. Fructose pentabenzoate, m.p. 78-79°, may be similarly prepared. 

In spite of their easy interconversion in solution a and p forms of carbohydrates are capable of independent existence and many have been isolated m pure form as crys talline solids When crystallized from ethanol d glucose yields a d glucopyranose mp 146°C [a]o +112 2° Crystallization from a water-ethanol mixture produces p d glucopyranose mp 148-155°C [aj +18 7° In the solid state the two forms do not mterconvert and are stable indefinitely Their structures have been unambiguously con firmed by X ray crystallography... 

A final example of application and process layout is shown in Figure 15. In this example the process relies on activated carbon to remove color bodies from a recycled glucose intermediary prior to use in the production of confectionary. The glucose containing the color taint must be mildly heated (to about 70° C), so that the normally solid product becomes less viscous and easier to pump. The syrup is... 

In spite of theii easy interconversion in solution, a and p fonns of carbohydrates are capable of independent existence, and many have been isolated in pure fonn as crystalline solids. When crystallized from ethanol, D-glucose yields a-D-glucopyianose, mp 146°C, [a]o -1-112.2°. Crystallization from a water-ethanol mixture produces P-d-glucopyranose, mp 148-155°C, +18.7°. In the solid state the two fonns do not... 

The following process description is taken from U.S. Patent 2,897,218. Six 100-ml portions of a medium in 250-ml Erlenmeyer flasks containing 1% glucose, 2% corn steep liquor (60% solids) and tap water was adjusted to a pH of 4.9. This medium was sterilized for 45 minutes at 15 psi pressure and inoculated with a one to two day growth of Septomyxa affinis ATCC 6737. The Erlenmeyer flasks were shaken at room temperature at about 24°C for a period of 3 days. 

In extending this direct method of synthesis, we next investigated the possibility of preparing similarly constituted halides from 2-deoxy-D-arabino-hexose (2-deoxy-D-glucose) (21). The hexose was subjected to a partial anomerization procedure described by Bergmann and co-workers (1). The solid material obtained by this procedure is a mixture of the anomeric forms of 2-deoxy-D-arabino-hexose low temperature p-nitro-benzoylation of the latter in pyridine resulted in a mixture of crystalline, anomeric tetrakis-p-nitrobenzoates in a ratio of approximately 1 1. They were readily separable by fractional recrystallization, and treatment of either with an excess of hydrogen bromide in dichloromethane, or with... 

Sorbitol is produced by a gas-liquid-particle process in which a solution of glucose is hydrogenated in the presence of a solid catalyst consisting of nickel on diatomaceous earth carrier (B6). 

Glucose, benzophenone (C6HsCOC6H5), and methane are examples of compounds that form molecular solids. The structures of glucose and benzophenone are given here. 

If we add only a small amount—20 g, for instance—of glucose to 100 mL of water at room temperature, it all dissolves. However, if we add 200 g, some glucose remains undissolved (Fig. 8.16). A solution is said to be saturated when the solvent has dissolved all the solute that it can and some undissolved solute remains. The concentration of solid solute in a saturated solution has reached its greatest value and no more can dissolve. The molar solubility, s, of a substance is its molar concentration in a saturated solution. In other words, the molar solubility of a substance represents the limit of its ability to dissolve in a given quantity of solvent. 

Wood chips can also be utilized as such to produce bioethanol. The cellulose and hemicellulose material is hydrolyzed in the presence of acids (H2SO4, HCl, or HCOOH) or enzymes to yield glucose and other monosaccharides [16]. Lignin is separated by filtration as a solid residue and the monosaccharides are fermented to ethanol, which, in turn, is separated from water and catalyst by distillation. Ethanol can be used not only as energy source but also as a platform component to make various chemicals, such as ethene and polyethene. Today green acetaldehyde and acetic acid from wood-derived bioethanol is manufactured by SEKAB Ab, at the Ornskoldsvik Biorefinery of the Future industrial park. 

The molecules of a molecular solid retain their individual properties. Solid I2, for example, is dark in color because individual I2 molecules absorb visible light, as shown by the fact that I2 vapor also is colored. Glucose dissolved in coffee tastes just as sweet as solid glucose because the sweet taste of glucose comes from its shape, which is the same in the solid phase as it is in solution. 

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