Iris polysaccharide

Jones and coworkers, in studies on mannose-containing polysaccharides, have isolated, from seeds of Iris ochroleuca and Iris sibirica, heterogeneous polysaccharides yielding on hydrolysis D-glucose and D-mannose in approximately equal amounts, as well as D-galactose (m. 3 %). These workers consider the possibility that the polysaccharides are mixtures of glucomannan with galactomannan, but, because of the similarity (in composition) between the two iris polysaccharides, tend to the view that they are... 

Similarly-constituted glucomannans have been isolated from various species of iris seeds107 and lily bulbs,108 the polysaccharides containing D-glucose and D-mannose residues in the proportions 1 1.1 and 1 1.9, respectively. The iris-seed glucomannans also contain a small proportion of D-galactopyranose end-groups.107... 

Mannose-containing Polysaccharides. Part III. The Polysaccharides in the Seeds of Iris ochroleuca and I. sibirca, P. Andrews, L. Hough, and J. K. N. Jones,/. Chem. Soc.,... 

A number of polysaccharides which yield D-glucose and D-mannose on hydrolysis have been described. The flour extracted from the conns of Amorphophattus konjak, which is used as a food in the Far East, contains a glucomannoglycan(2 3), konjakmannan. The molecule has a (i - -4)-linked main chain, with branches linked (i - 3), and has lo-ii residues per terminal unit. Glucomannoglycans have been found in other AmorphophdUus species, and in the seeds of some Iris species. 

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