茶叶中稀土元素结合多糖的结构特征及某些生物活性

Structure Characteristics and Some Bio-activities of Ree Binding Polysaccharides from Tea

随着稀土农用面积的增大,人们日益关注稀土在植物性可食部分中存在的状态及稀土结合的生物大分子的生物活性。本文应用ICP-MS、NMR及EXAFS等分析方法测得成品茶叶中含有稀土结合多糖(REE-BPS),其稀土元素(REE)含量随喷施稀土的次数的增加而明显增多,尤其是La。REE-BPS中La原子的第一配位层是六配位的氧原子,平均键长距离2.52A;第二配位层是三配位的硫原子,平均距离2.91A。REE-BPS具有明显的降血糖效果和增强机体免疫作用等活性。

States of existing in edible parts and bio-activities of rare earth elementsREEbinding macromolecule from crop have drawn greatly attention with the expansion of the applying of REE to agriculture. Results studied by ICP-MS, NMR and EXAFS showed that REE binding polysaccharides REE-BPScomplex existed in tea. The contents of REE especially La in REE-BPS were evidently increased by spraying REE. The coordination atom of the first coordination shell of La in REE-BPS was oxygen whose coordination number was 6 and the average distance among the atoms was 2.52 , and the second shell was sulfur that were 3 and 2.91 respectively. REE-BPS had effects of decreasing blood glucose in mice, both normal and high blood glucose mice, and enhancing immunization of mice and rats.