Monosaccharide composition

The aerial part of sage was successively extracted with water, potassium oxalate, DMSO and KOH, and gave rise to different fractions with bioactivity. Partial purification of the water extract gave rise to a polydisperse fraction called A, that based on the monosaccharide composition, IR, and NMR, was thought to be composed of arabinogalactans associated with the highly ramified rhamnogalacturonans core. Fracfion B, exfracfed wifh oxalate, was... 

The monosaccharide composition of all the samples was determined by GLC analysis of the trimethylsilyl methyl glycoside derivatives [1]. 

Monosaccharides composition of pectic polysaccharides in different tissue zones of apple... 

In the present study we used transgenic plants to analyse the amount of control exerted by an additional vacuolar invertase on the allocation of carbohydrates to the plant cell wall. Since physical parameters indicated a significant modification in the thermodynamic state of these invertase plants, the monosaccharide composition, the pore size and the amount of free and bound acids present in the cell wall were measured. 

Yokota, H., Mori, K., Yamaguchi, H., Kaniwa, H., and Saisho, N., Monosaccharide composition of palmiteplase by anion exchange chromatography with pulsed amperometric detection, /. Pharm. Biomed. Anal., 21, 767, 1999. 

The quality of this library was examined by monosaccharide compositional analysis. A portion of the trisaccharide library was treated with aqueous trifluroacetic acid at 100°C for 4 h. Analysis of the resulting mixture of monosaccharides on a Dionex HPLC system with a PA1 column and pulsed amperometric detection (PAD) showed that galactose, glucose, and mannose were present in approximately the required ratio. 

For monitoring the extent of polysaccharide hydrolysis, l.c. methods that sepeu ate and analyze the non-fermentable oligosaccharides (d.p. 3-30) derived from cellulose, hemicellulose, and pectins are useful, and have already been described (see Section III,l,c). For determination of the monosaccharide composition of completely hydrolyzed, plant polysaccharides, l.c. is especially useful and has been applied to the compositional analysis of hydrolyzed plant fiber,wood pulps,plant cell-walls,and cotton fibers.In these representative examples, the major sugars of interest, namely, glucose, xylose, galactose, arabinose, and mannose, have traditionally been difficult to resolve by l.c. The separa-... 

In recent years, Hardell and Westermark (6) scratched Picea abies tracheids with tweezers, collected individual cell wall layers, and then analyzed the average monosaccharide composition. Surprisingly, among the individual cell wall layers no significant difference in the mannose xylose glucose ratio among individual cell wall layers was observed. 

The monosaccharide composition of the hemicelluloses, which were a major fraction of all of these cell wall preparations, also showed significant differences, especially in the amounts of glucose and galactose (Table II). 

While the hemicelluloses obtained from the germ, aleuron, and caryopsis coat cell walls all showed a similar monosaccharide composition, this was not the case for the endosperm tissue. Thus, a major difference in the structure of hemicellulosic polysaccharides exists between the preparations obtained from the endosperm cell walls and those from the cell walls of the other parts of the grain, i.e., rice bran. (Rice bran consists of the caryopsis coat, aleuron layer and germ.) Comparison of the detailed structural features of the hemicellulosic polysaccharides of endosperm and bran cell walls will be discussed in the following sections. 

Table II. Monosaccharide Composition of Pectic Polysaccharides and Hemi-cellulose Obtained from Different Cell Wall Preparations...

Apart from the complexity of its monosaccharide composition and the presence of the mannose 6-phosphate derivative, this glycolipid is also unusual, in that fucose is located inside the oligosaccharide chain, which is the first time that this has been found in glycolipids. 

Determination of the monosaccharide composition by gas chromatography of alditol acetates is commonly used for cell wall analyses because the procedure gives a single peak for each sugar. An alternative is to prepare trimethylsilyl (TMS) derivatives. However, these are easily hydrolyzed by moisture in the atmosphere and therefore should be analyzed in the gas chromatograph immediately, whereas alditol acetates are relatively more stable and could be rerun on the gas chromatograph the following day if required. 

In this procedure, the cell walls are first treated with TFA to determine the neutral monosaccharide composition of the noncellulosic polysaccharides. The TFA-insoluble residue is then hydrolyzed using a two-stage sulfuric acid procedure to determine cellulose content. 

Harris, P.J., Blakeney, A.B., Henry, R.J., and Stone, B.A. 1988. Gas chromatographic determination of the monosaccharide composition of plant cell wall preparations. J. Assoc. Off. Anal. Chem. 71 272-275. 

Murayama, S. (1984). Changes in the monosaccharide composition during the decomposition of straws under field conditions. Soil Sci. Plant Nutr. 30, 367-381. 

The total monosaccharide composition of OCL acid posthydrolysate is approx 26 g/L of monosaccharides, with a ratio of 2 5 3 for glucose xylose arabinose. Compared to other hydrolysates, it has higher arabinose but lower xylose contents than rice straw (37), sugarcane bagasse (38), Eucalyptus wood (16), and corncobs (36), where the latter two hydrolysates were also obtained in a similar two-step procedure. Nevertheless, the total monosaccharide content is in the same range, e.g., as rice straw, Eucalyptus wood, or corncobs. 

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