REE BOUND POLYSACCHARIDES IN LEAVES OF DICRANOPTERIS-DICHOTOMA BY MAA

The binding of REEs with polysaccharides (PSs) in the leaves of fern D icranopteris dichotoma (DD) has been studied by molecular activation a nalysis (MAA). The PSs of different solubilities in the leaves of DD, which were named cold-water-soluble, hot-water-soluble, acidic-soluble and basic-soluble PSs, were obtained using biochemical separation tec hniques. After deproteinization and gel permeation chromatography sepa ration, the absorption curves of the PSs were obtained by colorimetry. The eight REEs (La, Ce, Nd, Sm, Eu, Tb, Yb,and Lu) were also detected in the PSs by neutron activation analysis (NAA). The results obtained showed that the REEs were bound firmly with the PSs in the leaves of DD. The molecular weight measurement on Sephadex G-200 demonstrated th at those PSs bound with REEs were mostly small molecular weight polysa ccharides (10000 to 20000 u).