Monosaccharides common

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. 

Monosaccharides commonly form internal hemiacetals or hemiketals, in which the aldehyde or ketone group joins with a hydroxyl group of the same molecule, creating a cyclic structure this can be represented as a Haworth perspective formula. The carbon atom originally found in the aldehyde or ketone group (the anomeric carbon) can assume either of two configurations, a and /3, which are interconvertible by mutarotation. In the linear form, which is in equilibrium with the cyclized forms, the anomeric carbon is easily oxidized. 

Galactose. A monosaccharide commonly occurring in milk sugar or lactose. Formula. G Hi C>6. 

Table F1.4.7 Typical1H-1 H Coupling Constants for the Monosaccharides Commonly Identified in Anthocyanins ...

Table Fl.4.7 contains typical H- H coupling constants for the monosaccharides commonly identified in anthocyanins. When the ring size of the anthocyanin monosaccharides has been reported, all but one have been reported as pyranoses (arabinofuranosyl has been identified in zebrinin Idaka et al., 1987). When examined, the anomeric configurations of the glucosyl, galactosyl, xylosyl and glucuronyl...

Monosaccharides, commonly found in foods, are hexoses. Most monosaccharides can be fermented. 

GLC is a versatile and widely used method for the separation of volatile sugar derivatives. Although a number of derivatives have found application, the most commonly used derivative is the alditol acetate which gives a single peak for each sugar (Sawardeker et al., 1965). The monosaccharides commonly found in plant cell walls can, as their alditol acetates, be separated readily on a number of commercially available liquid phases such as OV-225 (Selvendran et al., 1979) and SP-2330 (Englyst et al.,... 

FIGURE 5.10 Examples of monosaccharides commonly found in soils. 

Figure 1. Separation by GLC of monosaccharides commonly occurring in glycoproteins run as the 0-TMS ethers of the methyl glycosides. The chromatograph was temperature-programmed from 140° to 200° at 0.5°/min. The peaks are numbered in their order of emergence and are identified as follows fucose 1,2,3 xylose 4,5 (Arabi-nitol 6) mannose 7,9 galactose 8,10,11 glucose 12,13 (Mannitol 14) AT-acetyl-glucosamine 15,17,19,20 iV-acetylgalactosamine 16,18 (Perseitol 21) methyl -acetylneuraminate 22.

Molar Adjustment Factors of Monosaccharides Commonly Occurring in Glycoproteins and Glycopeptides"... 

These are glycosides of N-acyl long-chain bases (ceramides). Galactose and glucose are the monosaccharides commonly found. The structures of two representative molecules - one from mammalian brain and the other from a higher plant - are shown below. 

L-Fucose, one of several monosaccharides commonly found in the surface polysaccharides of animal cells (Chemical Connections 17B), is synthesized biochemically from D-mannose in the following eight steps ... 

Monosaccharides consist of only one sugar unit. Oligosaccharides consist of between two and ten of the same or different monosaccharides connected to each other by glycosidic (semiacetal) bonds. Monosaccharides and oligosaccharides are sometimes referred to collectively by the name sugars, as they share many common properties and often have a sweet taste. Polysaccharides are composed of more than ten of the same or different monosaccharides commonly they consist of multiple molecules of monosaccharides, which are often precisely determined. Complex carbohydrates also contain compounds other than saccharides, such as, for example, peptides, proteins and lipids. 

Mono- to trl-saccharldes in honey have been identified and assayed by separate analysis of their pertrlmethyIslly1 ethers before and after formation of oxime derivatives. The dual system was employed to account for overlapping peaks, and sixteen components including two trisaccharides were identified.A good separation of the neutral monosaccharides commonly present in glycoproteins was achieved using their acetylated 0 -(pentafluoro-... 

Fructose, the monosaccharide commonly called fruit sugar, is about 50 percent sweeter than sucrose, the disaccharide familiarly known as table sugar. Sucrose can be hydrolyzed to invert sugar which is a mixture of fructose and glucose. Liquid invert sugar has been the major sweetener used in soft drinks and as a food ingredient. 

Figure 27.13 Monosaccharides commonly found in oligosaccharide chains in glycoproteins and glycosidic determinants of blood groups.

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