The main sugars making up the carbohydrate are galactose and glucose while other sugars such as xylose, arabinose and mannose are also present in smaller quantities.
en.wikipedia.org Simple sugars are called monosaccharides and include glucose (also known as dextrose), fructose and galactose.
en.wikipedia.org However, galactose concentration must be fairly high before the enzyme, aldose reductase, will convert significant amounts of the sugar to its galactitol form.
en.wikipedia.org There is no problem with the metabolism of glucose or galactose, but fructose and glycerol can not be used as fuels.
en.wikipedia.org In contrast to cellulose, hemicellulose is derived from several sugars in addition to glucose, especially xylose but also including mannose, galactose, rhamnose, and arabinose.
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