Polysaccharides homogenization

Naturally occurring cellulose is a polydisperse linear homogeneous polysaccharide based on 1,4-D-glucopyranose repeat units, with an... 

Cellulosics. Cellulose is the major chemical constituent of plants. It is a homogeneous polysaccharide formed from /3- D-glucopyranose units linked together... 

Yeast mannan is an amorphous, homogeneous polysaccharide with a D. P. of about 500. The proposed structure of this mannan is a long chain, with radiating side-chains of one or two D-mannopyranose units. In this mannan, 2 —> 1, 3 —> 1, and 6 — 1 linkages have been found. The mannan of the seaweed Porphyra umbilicalis contains chiefly 4 —> 1 /3-d linkages, and is of the branched-chain type with about one branch for each 12 D-mannose residues. 

Homogeneous polysaccharides have not yet been obtained from... 

The success of separation into distinct homogeneous polysaccharides depends to no small extent, however, on the ease with which the initial extraction can be made. This raises the very important subsidiary question of the effect of the extraction procedure on the polysaccharide itself. Extraction procedures may modify (1) the actual structure of the molecule, or (2) the molecular-weight distribution, or both. Such problems are particularly pertinent in the hemicellulose and the mucopolysaccharide fields. Earlier Chapters in this Series have mentioned some aspects of these problems, whilst the effect of delignification has been discussed by Lindberg. These problems are not considered further here, but it should be noted that the effect of variation of isolation procedure on molecular weight and its distribution can only be followed by physical methods (as in the case of glycogen ),... 

Polysaccharides have also been obtained from cell cultures of Echinacea purpurea, From the growth medium of . purpurea cell cultures, three homogeneous polysaccharides, i.e. two neutral fucogalactoxyloglucans with MW of 10,000 and... 

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