ICP-MS法测定茶叶及其多糖提取物中的降血糖相关性元素

采用微波溶样ICP-MS法测定了江西婺源绿茶茶叶、茶叶温水及热水浸提液和茶多糖中降血糖相关性元素(ERBS)的含量，探讨了ERBS含量与茶叶品质老嫩以及茶多糖中ERBS含量与茶叶中ERBS总量的关系。结果表明，茶叶品质老嫩不同，茶叶以及茶多糖中各ERBS含量存在一定差异，由品质差的茶叶提取得到的茶多糖中的ERBS的量较高。茶叶中结合于多糖中的各ERBS占相应ERBS总量的比例在0.03%～9.57%之间，与元素种类、茶叶品质有关。结合于多糖中的ERBS占茶叶ERBS总量的比例，鄣山特级和五级茶分别为1.11%和2.10%，对孤山老叶茶，为0.85%。测定结果可以作为选择提取茶多糖茶叶原料的依据，也可为研究茶多糖可能的降血糖机理提供可靠的无机元素方面的数据。

Determination of Elements Related to Reducing Blood Sugar (ERBS)in Tea and Tea Polysaccharide by ICP-MS

Contents of elements related to reducing blood sugar (ERBS) in several kinds of green tea of Wuyuan county, their tea infusion extracted by warm water and boiling water and tea polysaccharide (TP) were determined by ICP-MS, after the samples were digested with acids by microwave method. The relation between the amount of ERBS and tea quality and the relation between the content of ERBS in TP and the total content in tea were discussed. The results showed that the amounts of ERBS in tea and TP are different in various samples. The amount of ERBS in TP extracted from coarse tea was higher than that from fresh tea. The percentage of certain ERBS in TP accounting for the ERBS in tea ranged from 0.03% to 9.57%. As to the total ERBS in TP extracted from Mt. Zhang super grade tea and grade 5 tea, the percentages were 1.11% and 2.10% respectively. As to Mt. Gu old tea, it was 0.85%. The results could provide data for selecting tea material used to extracting tea polysaccharide and for studying the mechanism of reducing blood sugar.