hemicellulose hem·i·cel·lu·lose (hěm'ĭ-sěl'yə-lōs', -lōz')
Any of several polysaccharides that are more complex than a sugar and less complex than cellulose and found in plant cell walls.
any of a group of complex carbohydrates that, with other carbohydrates (e.g., pectins), surround the cellulose fibres of plant cells. The most common hemicelluloses contain xylans (many molecules of the five-carbon sugar xylose linked together), a uronic acid (i.e., sugar acid), and arabinose (another five-carbon sugar). Hemicelluloses have no chemical relationship to cellulose.
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