Water glucose and

CH 20. CHOCH(CH OH)CHOH. CHOH.CHOHj mw 386.36 / form, cryst, mp 131 8u- It was prepd from glycol, glucose, water and emulsin (Ref 4)... 

Amerov AK, Chen J, Arnold MA. Molar absorptivities of glucose, water and other biological molecules over the first overtone and combination regions of the near infrared spectrum. Applied Spectroscopy 2004, 58, 1195-1204. 

Fig. 2.1 During photosynthesis, the energy of sunlight is used to rearrange the components of carbon dioxide and water molecules to form glucose, water, and oxygen.

Isoamylase is produced by pure culture fermentation of the production strain P. amyloderamosa MU 1174. It is secreted into the fermentation medium, from which it is recovered and concentrated. It is subsequently stabilized, formulated and standardized with maltose, glucose, water and either glycerol fatty acids or sodium benzoate. In the preparation named Isoamylase M , glycerol n-caproate and glycerol octylate are used in Isoamylase S , sodium benzoate is used. 

Typical results for (a) urea-water, (b) glucose-water and (c) sucrose-water system are given in Fig. 11.8. 

Colourless crystals m.p. I25°C, soluble in water and alcohol. In aqueous solution forms equilibrium with its lactones. Gluconic acid is made by the oxidation of glucose by halogens, by electrolysis, by various moulds or by bacteria of the Acetobacter groups. 

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. 

Reduction of ammoniacal silver nitrate. Place 2 ml. of dilute silver nitrate solution in a clean test-tube. Add 1 drop of NaOH solution and then add dil. ammonia drop by drop until the precipitate formed by the NaOH is just not redissolved. Now add 1-2 ml. of glucose solution and place the test-tube in a water-bath at 50-60° a silver mirror is produced in 1 - 2 minutes. 

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. 

Of all the monosaccharides d (+) glucose is the best known most important and most abundant Its formation from carbon dioxide water and sunlight is the central theme of photosynthesis Carbohydrate formation by photosynthesis is estimated to be on the order of 10 tons per year a source of stored energy utilized directly or indi rectly by all higher forms of life on the planet Glucose was isolated from raisins m 1747 and by hydrolysis of starch m 1811 Its structure was determined in work culmi nating m 1900 by Emil Fischer... 

Barfoed s reagent (test for glucose) dissolve 66 g of cupric acetate and 10 mL of glacial acetic acid in water and dilute to 1 liter. 

Benedict s qualitative reagent (for glucose) dissolve 173 g of sodium citrate and 100 g of anhydrous sodium carbonate in about 600 mL of water, and dilute to 850 mL dissolve 17.3 g of CUSO4 5H2O in 100 mL of water and dilute to 150 mL this solution is added to the citrate-carbonate solution with constant stirring. See also the quantitative reagent below. 

Metformin. Metformin [657-24-9] (1,1-dimethylbiguanide), mol wt 129.17, forms crystals from propanol, mp 218—220°C, and is soluble in water and 95% ethanol, but practically insoluble in ether and chloroform. Metformin, an investigational dmg in the United States, does not increase basal or meal-stimulated insulin secretion. It lowers blood glucose levels in hyperglycemic patients with Type II diabetes but has no effect on blood glucose levels in normal subjects. It does not cause hypoglycemia. Successful metformin therapy usually is associated with no or some weight loss. 

Pure D-fmctose is a white, hygroscopic, crystalline substance and should not be confused with the high fmctose com symps (HFCS) which may contain 42—90 wt % fmctose and 23—29% water (8,9). The nonfmctose part of these symps is glucose (dextrose) plus small amounts of glucose oligomers and polymers. Fmctose is highly soluble ia water at 20°C it is 79% soluble, compared with only 47% for glucose and 67% for sucrose. 

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