Gum Tragacanth

Structure


Monomer sequence:


D-galactose, D-galacturonic acid, L-fucose, D-xylose, L-arabinose (ratio not known). The acidic components are largely present as calcium, magnesium and potassium salts. It is believed that the gum is composed of the two components bassorin (60-70%, water insoluble) and tragacanthin (30-40%, water soluble). It has been suggested, that bassorin is complex structure of polymethoxylated acids, that om demethoxylation, probably yields tragacanthin. Tragacanthin consists of a ring containing three molecules of glucoronic acid and one molecule of arabinose, with a side chain of two molecules of arabinose [1].