Straw hemicelluloses, structure

The search for structure-function relationships was carried into many other areas of the polysaccharides, including glycogen (with M. Abdel-Akher and 0. P. Bahl) hemicelluloses of wheat straw and corn cobs (with... 

Hemicelluloses are noncellulose materials produced by plants and found in straw, wood, and other fibrous tissues. Xylans are the most abundant hemicelluloses. They consist of l,4-)3-linked o-xylopyranoses. Draw the structure for the repeating unit in xylans. 

Chemical components of wheat straw can be divided into cellulose, hemicellulose, lignin and extractives. The content and structure of each component for wheat straw are very different to those for wood. TG results are given in Table 9.9. 

Similarly wheat straw, another annually replenishable biomass resource available in many countries, contains about 35-38% hemicellulose (Sun and Tomkinson, 2002). Extraction of this hemicellulose, containing about 70% xylose, 13% arabinose and 14% gluclose by an ultrasound irradiation technique, improved the molecular weight as well as the thermal stability of the hemicellulose, and is a promising technique if used in conjunction with other techniques such as steam explosion . This will enable the extraction of hemicellulose in such a form that the chemical structure will be as little changed as possible from the native state. 

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