Of dextrose

Fructose—Dextrose Separation. Emctose—dextrose separation is an example of the appHcation of adsorption to nonhydrocarbon systems. An aqueous solution of the isomeric monosaccharide sugars, C H 2Dg, fmctose and dextrose (glucose), accompanied by minor quantities of polysaccharides, is produced commercially under the designation of "high" fmctose com symp by the enzymatic conversion of cornstarch. Because fmctose has about double the sweetness index of dextrose, the separation of fmctose from this mixture and the recycling of dextrose for further enzymatic conversion to fmctose is of commercial interest (see Sugar Sweeteners). 

Dextrose (D-glucose) is by far the most abundant sugar in nature. It occurs either in the monosaccharide form (free state) or in a polymeric form of anhydrodextrose units. As a monosaccharide, dextrose is present in substantial quantities in honey, fmits, and berries. As a polymer, dextrose occurs in starch, cellulose (qv), and glycogen. Sucrose is a disaccharide of dextrose and fmctose. 

Properties. Physical properties of the three crystalline forms of dextrose are Hsted in Table 1. In solution, dextrose exists in both the a- and P-forms. When a-dextrose dissolves in water, its optical rotation, [cc], diminishes gradually as a result of mutarotation until, after a prolonged time, an... 

Dextrose in solution or in soHd form exists in the pyranose stmctural conformation. In solution, a small amount of the open-chain aldehyde form exists in equiUbrium with the cycHc stmctures (1) and (2). The open-chain form is responsible for the reducing properties of dextrose. 

The reaction of dextrose with a nitrogen-containing compound, eg, amino acids or proteins, yields a series of intermediates which form pigments of varied molecular weight (Maikard reaction). The type of pigments produced is dependent on reaction conditions such as pH, temperature, and concentration of reactants. 

Table 3. Yearly Price of Dextrose, HFS, and Com Symp in the United States, /kg...

Health Factors. Dextrose products are substances that are presumed to be GRAS by the FDA (21). A study of the health aspects of dextrose, fmctose, and com symps has indicated that these sweeteners are not hazardous at levels of normal human consumption with the exception of a small contribution to the formation of dental caries (22). 

Uses. The main use of dextrose is in food processing (qv), where it is of value for its physical, chemical, and nutritive properties. Dextrose is also used in nonfood appHcations in the chemical, dmg, and pharmaceutical industries. This latter segment of the market represents about 21% of dextrose... 

High fmctose com symps (HFS, HFCS, isosymp, isoglucose) are concentrated carbohydrate solutions containing primarily fmctose and dextrose as well as lesser quantities of higher molecular weight saccharides. A 42 wt % fmctose symp is produced by partial enzymatic isomerization of dextrose hydrolyzate. 

Sweetness is primarily a function of the levels of dextrose and maltose present and therefore is related to DE. Other properties that increase with increasing DE value are flavor enhancement, flavor transfer, freezing-point depression, and osmotic pressure. Properties that increase with decreasing DE value are bodying contribution, cohesiveness, foam stabilization, and prevention of sugar crystallization. Com symp functional properties have been described in detail (52). 

In the canning and preserving industries, com symps are used to prevent crystallization of sucrose, provide body, accentuate tme fmit flavors, and improve color and texture. In the beverage industry, the predominant use is in the beer and malt-Hquor areas. High conversion symps are used to replace dry cereal adjuncts, provide fermentable sugars, enhance flavor, and provide body. These symps contain controlled amounts of dextrose and maltose for proper fermentation. 

Crystalline D-fmctose also finds use in the food industry. The annual consumption, in the United States, of dextrose is >600,000 tons and of HFCS... 

Intravenous replacement solutions are a source of electrolytes and water for hydration (Normosol M Ringer s Injection, Lactated Ringer s, Plasma-Lyte R), and used to facilitate amino acid utilization and maintain electrolyte balance (Lypholyte, Multilyte, TPN Electrolytes). Dextrose and electrolyte solutions such as Plasma-Lyte R and 5% dextrose are used as a parenteral source of electrolytes, calories, or water for hydration. Invert sugar-electrolyte solutions, such as Multiple Electrolytes and Travert 5% and 10%, contain equal parts of dextrose and fructose and are used as a source of calories and hydration. 

Hyperglycemia is the most common metabolic complication. A too rapid infuson of amino add-carbohydrate mixtures may result in hyperglycemia, glycosuria, mental confuson, and loss of consciousness Blood glucose levels may be obtained every 4 to 6 hours to monitor for hyperglycemia and guide the dosage of dextrose and insulin (if required). To minimize these complications the primary health care provider may decrease the rate of administration, reduce the dextrose concentration, or administer insulin. 

To prevent a rebound hypoglycemic reaction from the sudden withdrawal of TPN containing a concentrated dose of dextrose, the rate of administration is slowly reduced or the concentration of dextrose gradually decreased. If TPN must be abruptly withdrawn, a solution of 5% or 10% dextrose is begun to gradually reduce the amount of dextrose administered. 

The conversion of dextrose syrups to high-fruotose oorn syrups... 

Strict avoidance of hypoglycemia. Ensure an adequate source of dextrose in any patient receiving an insulin product... 

Should be used with a continuous enteral or intravenous source of dextrose... 

Parenteral product should be mixed with saline instead of dextrose diluents... 

Intravenous lipid emulsions are also a source of calories. The typical daily dose in adults is approximately 0.5 to 1 g/kg per day. In the absence of hypertriglyceridemia, substituting a portion of dextrose calories with lipid calories may be beneficial in situations where dextrose infusion may lead to complications (e.g., hyperglycemia). Some examples include patients with diabetes mellitus or pancreatic disease and patients under severe stress (e.g., trauma or burns) who are at risk for hyperglycemia. The maximum of dose of lipid emulsions is 2.5 g/kg per day,7 or 60% of total daily calories, although doses this high are used rarely in practice. 

Commonly administered LVPs include such products as Lactated Ringers Injection USP, Sodium Chloride Injection USP (0.9%), which replenish fluids and electrolytes, and Dextrose Injection USP (5%), which provides fluid plus nutrition (calories), or various combinations of dextrose and saline. In addition, numerous other nutrient and ionic solutions are available for clinical use, the most popular of which are solutions of essential amino acids or lipid emulsions. These solutions are modified to be hypertonic, isotonic, or hypotonic to aid in maintaining both fluid, nutritional, and electrolyte balance in a particular patient according to need. Indwelling needles or catheters are required in LVP administration. Care must be taken to avoid local or systemic infections or thrombophlebitis owing to faulty injection or administration technique. 

In kinetic studies of enzymatic reactions, rate data are usually tested to determine if the reaction follows the Michaelis-Menten model of enzyme-substrate interaction. Weetall and Havewala [Biotechnol. and Bioeng. Symposium 3 (241), 1972] have studied the production of dextrose from cornstarch using conventional... 

A micro-bomb calorimeter exploded when the wrong proportions of sample and oxidants were used. Instead of 4 g of peroxide and 0.2 g of nitrate for 0.2 g of the sugar sample, 0.35 g of peroxide and 2.6 g of dextrose were used. The deficiency of peroxide to absorb the decomposition gases and excess of organic matter led to a rapid rise in temperature and pressure, which burst the bomb calorimeter. 

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