Unknown Polysaccharides of Softwood

All of the major polysaccharides in softwoods are now known these are cellulose, galactoglucomannans, arabino-(4-0-methylglucurono)xylan, ara-binogalactan, galactan, pectic material, and starch. It is clear, however, that other minor polysaccharide constituents, still unknown, must also be present. These polysaccharides have not yet been isolated, but their presence may be inferred from the formation of di- and tri-saccharides of unknown origin on partial hydrolysis of wood or crude hemicellulose preparations. 

In their extensive investigations on the acid oligosaccharides produced on partial hydrolysis of wood of maritime pine, Roudier and Eberhard isolated several aldobiouronic acids of as-yet-unknown origin. One of 

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