Abstract: The composition and property of polysaccharide gums in seeds of fenugreek, Gleditsia sinensis Lam., G. microphylla Gordon ex Y.T.Lee and tara have been first analysed systematically. It is determined that the mass contents of endosperm in seed are 33.1%, 37.8%, 41.3% and 30.5%, respectively, and the polysaccharide contents of endosperms are 74.6%, 68.6%, 63.0% and 78.0%, respectively. The polysaccharides isolated from these seeds are composed of galactose and mannose, which is similar to galactomannan from guar gum. The endothermic peaks of differential thermal analysis (DSC) of these polysaccharides are 325.5, 314.8, 309.6 and 313.6℃, and the enthalpies are 88.6, 114.4, 71.6 and 84.1 J/g respectively. The viscosity of G. sinensis polysaccharide gum at 1% concentration is the highest (274 mPa·s). Fenugreek polysaccharide gum has the lowest water insoluble substance of 8.5% (mass fraction). The aqueous solution of polysaccharide gum will gel in the presence of borate under alkalinic condition, and the jelly viscosity of fenugreek polysaccharide is 5940 Pa·s, which is the highest among other galactomannans.

Key words: fenugreek, Gleditsia sinensis Lam., Gleditsia microphylla Gordon ex Y.T.Lee, tara, polysaccharide gum