我国主要植物多糖胶资源组成比较研究

Study on Composition of Plant Polysaccharide Gums as Main Resources in China

研究了胡芦巴、皂荚、野皂荚与塔拉种子组分和多糖胶性质。种子胚乳质量分数分别为33.1%、37.8%、41.3%和30.5%;种子胚乳中聚糖质量分数分别为74.6%、68.6%、63.0%和78.0%;多糖结构与瓜尔多糖类似,均为半乳甘露聚糖,多糖差示扫描量热分析(DSC)图谱对应的热裂解峰温分别为325.5、314.8、309.6和313.6℃,热裂解吸热量分别为88.6、114.4、71.6和84.1 J/g。质量分数1%的各种胶液黏度中皂荚多糖胶的表观黏度值最高(274 mPa.s);胡芦巴多糖胶水不溶物质量分数最低(8.5%)。多糖胶与硼离子形成的冻胶,其黏度因多糖胶品种而异,其中质量分数1%的胡芦巴冻胶黏度最高,其值为5 940 Pa.s。

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 84.1J/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.