Maltose formula

Carbohydrates may be divided into monosaccharides, disaccharides and polysaccharides. The monosaccharides under certain conditions react as polyhydroxy-aldehydes or polyhydroxy-ketones two important representatives are glucose CjHjjO (an aldose) and fructose (laevulose) CgHuO, (a ketose). Upon hydrolysis di- and polysaccharides 3deld ultimately monosaccharides. Common disaccharides are sucrose, lactose and maltose (all of molecular formula C,2H2. 0,), whilst starch, dextrin and cellulose, (CjHjoOj), in which n > 4, are typical polysaccharides. 

Write a chemical equation, using molecular formulas, for the reaction of maltose with water to form glucose. 

Early reports on levan are obscured by incomplete descriptions of impure products.2 96 Greig-Smith found that Bacillus levaniformans(1) produced levan from sucrose96" in suitable nutrient solutions, but not from D-glucose, D-fructose, lactose or maltose.966 He therefore assumed that levan could only be formed from the nascent D-fructose and D-glucose resulting from the inversion of sucrose. Hydrolysis of levan yielded D-fructose only, and analysis of levan agreed with the empirical formula (C HiriOi) it was noted that levan was closely related to inulin but was not identical with it. 

Two sugars can link to each other by losing water from OHs to form disaccharides. Figure 4.6 shows the Haworth projection formulas of four important disaccharides sucrose, lactose, maltose, and cellobiose, which all have the same molecular formulas, C12H22011. Sucrose and lactose are the most abundant and most important disaccharides of natural origin. Maltose and cellobiose are repeating units of polymeric starch and cellulose, respectively. Disaccharides may hydrolyze to form two monosaccharide molecules. 

Procedure Introduce equal volumes (20 jxL) of the Standard Solution and Assay Preparation into the chromatograph, and record the chromatograms. Note the retention times of the two major peaks exhibited by the Standard Solution, and calculate the ratio of the response of sucrose to that of the internal standard maltose. Calculate the quantity, in milligrams, of sucrose in the portion of sample taken by the formula... 

Here we compare the thermodynamic parameters of trehalose, maltose and sucrose because they have the same chemical formula (C12H22O11) and mass (molecular weight 342.3), but different structures which could be responsible for their different hydration properties. The anomaly of hydration of trehalose is understood from the following observation [10]. Namely, the amount of water used for the preparation of 1.5 M trehalose solution is smaller than the amount used for the preparation of other sugar solutions. In a 1.5 M solution, trehalose itself occupies 37.5% of the volume of the solution. However, in a 1.5 M solution, sucrose occupies 13% and maltose occupies 14%. These data suggest that trehalose has a larger hydrated volume than the other sugars. This hypothesis can be demonstrated from various thermodynamic parameters as shown in Table 12.1. 

Disaccharides are formed by the union of two monosaccharides with the loss of one molecule of water. Disaccharides include lactose, cellobiose, maltose, and sucrose. The molecular formula for sucrose is as follows ... 

Fig. 1.—I, maltose II, isomaltoac III, original Haworth formula IV, Staudinger formula V, origin of stable dextrins VI, modified Haworth formula VII, Meyer formula VIII, branched molecule IX-XII, end groups.

Maltose reduces Fehling s solution and therefore probably contains an aldehyde group. The constitutional formula is probably the same as that given for lactose. It yields an osazone which crystallizes in tufts of needles which are more blunt than the crystals of glucosazone. Maltose, like the other di-saccharoses does not ferment with yeast zymase. 

Starches are polysaccharides that have the generic formula (QHioOsJn. They are reserve sources of carbohydrate in some biomass, and are also made up of D-glucose units as shown by the results of hydrolysis experiments. But in contrast to the structure of cellulose, the hexose units are linked as in maltose, or glucose-a-glucoside (Fig. 3.6), as indicated by the results of partial hydrolysis. Another difference between celluloses and starches is that the latter can... 

The disaecharoses, having the chemical formula of C12H22O11, include sucrose, maltose, trehalose, melibiose, touranose and agavose. Of these sucrose is the most important. It is found in the stems of Digitized by Microsoft ... 

Problem 35.1 Formula I shows the structure of only the a-form of (+)-maltose. What is the structure of the /3-(+)-maltosc that in solution is in equilibrium with I ... 

Cyclic formula for Schardinger dextrins containing all maltose linkages... 

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