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Hemicelluloses and Their Derivatives

2003; American Chemical Society; Linguagem: Inglês

10.1021/bk-2004-0864.ch001

1947-5918

Run-Cang Sun, Sun Xiao, J. Tomkinson,

Advanced Cellulose Research Studies

Hemicelluloses are a large group of polysaccharides found in the primary and secondary cell walls of all land and fresh water plants, and in some seaweeds. The hemicelluloses, isolated from cereal straws, are largely represented as complex heteropolysaccharides whose structure varies in the nature and degree of branching of the β1,4-linked xylopyranosyl main chain. Hemicelluloses interconnect other cell wall components via covalent linkages and also secondary forces. In this review, the structural features and complexity of the hemicelluloses are illustrated Alkaline peroxide treatment provides a suitable and environmental friendly procedure for the isolation of hemicelluloses from different cereal straws and other agricultural residues. The esterification of hemicelluloses prepared under homogeneous reaction conditions in the presence of 4-dimethylaminopyridine or N-bromosuccinimide as a catalyst is summarized.