Maltose, chemical structure

Fig. 6 Chemical structure of maltose-polyrotaxane conjugates consisting of a-CDs, PEG, benzyloxycarbonyl-tyrosine and maltose (Mal-a/E20-TYRZs, 1-3), maltose-a-CD (4), and maltose-poly(acrylic acid) (5) conjugates [14]...

FIGURE 3.3 Chemical structure of the main soluble sugars found in cereal grains, (a) Glucose, (b) Fructose, (c) Sucrose, (d) Maltose, (e) Maltotriose. (f) Linear dextrin, (g) Branched dextrin. 

In order to gain some information about the fundamentals of the hydrothermal carbonization process, the hydrothermal carbonization of different carbohydrates and carbohydrate products was examined [12, 13]. For instance, hydrothermal carbons synthesized from diverse biomass (glucose, xylose, maltose, sucrose, amylopectin, starch) and biomass derivatives (HMF and furfural) were treated under hydrothermal conditions at 180 °C and were analyzed with respect to their chemical and morphological structures by SEM,13 C solid-state NMR and elemental analysis. This was combined with GC-MS experiments on residual liquor solutions to analyze side products... 

Chemical proof was given of the presence of the maltose structure in starch the high proportions of end groups in starch and glycogen, indicating highly ramified structures, were established, and later on attention was directed to methods for the separation of the amylose and amylopectin components of starches and to enzymatic transformations... 

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. 

FIGURE 4.2 C NMR of structures B and C (Fig. 4.1) of maltose-modified hyper-branched PEI showing the influence of different degrees of maltose attachment on hyperbranched PEI scaffold (Fig. 4.1). Source Appelhans et al. [3]. Reproduced with permission of American Chemical Society. 

Another common disaccharide is ceUobiose, obtained by the hydrolysis of cellulose (to be discussed in the next section). Its chemical properties are almost identical with those of maltose, and so is its structure, which differs only in the stereochemistry at the acetal linkage— instead of a. 

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