【作者】 孙继鹏；

【导师】 汪东风；

【作者基本信息】 中国海洋大学 ， 食品科学， 2006， 硕士

【摘要】 稀土元素可影响植物体内酶活、叶绿素的含量、矿质营养的代谢等,能促进作物的生长、发育可提高产量,对生理功能具有有益的作用。而且可以通过影响动物内脏器官免疫功能和内分泌系统,抑制肿瘤的生长和肺癌的发生率,并且还有降血糖、清除自由基等功效。但是在中性条件下,多数稀土元素会形成很稳定的氢氧化物的凝胶状沉淀,降低了稀土元素的溶解性,给它的应用带来了很大的局限性。最近的研究发现,稀土元素与多糖结合,可提高稀土元素的生物利用率,并发现这种糖稀土复合物具有降解磷酸酯的活性,尤其对有机磷农药有很好的降解效果,但是对于糖稀土配合物结构及有机磷农药的降解机理研究甚少。本论文合成了几种糖稀土复合物,在确定的试验条件下,比较了不同类型糖复合物对含磷酸酯键的对硝基磷酸苯二钠(pNPP2Na)水解活性,发现醛糖稀土复合物的水解活性要高于酮糖稀土复合物的活性,六碳糖复合物的水解活性要优于五碳糖复合物活性,其中葡萄糖-铈复合物对pNPP2Na的水解活性最高。在研究多糖稀土复合物对磷酸酯键的降解作用中发现,多糖稀土复合物对pNPP2Na的降解与多糖中醛糖含量有一定的关联,当多糖组成中醛糖尤其是六碳糖含量高时,则该多糖稀土复合物对磷酸酯键的水解活性比较明显。而且,多糖稀土复合物对磷酸酯键的降解与糖聚合度也有很大关系,随着多糖聚合度的升高,对磷酸酯键的降解活性反而降低。本论文还制备了葡萄糖稀土配合物GHS(葡萄糖-硫酸高铈复合物)和GHN(葡萄糖-硝酸铈铵复合物),果糖稀土配合物FHS(果糖-硫酸高铈复合物)和FHN(果糖-硝酸铈铵复合物),并经过硅胶柱层析和Sephadex G25凝胶柱层析对其分离纯化,通过HPLC进一步分离和纯度鉴定,再通过结晶得到GHS晶体。采用紫外可见光谱、荧光光谱和X射线粉末衍射法对糖复合物的结构进行了初步探讨,证实糖环上羟基可与稀土元素结合形成糖稀土复合物。对所制备的糖稀土复合更多还原

【Abstract】 The rare earth elements (REE) have effects on immune-related enzyme activities, content of chlorophyll and the mineral nutrition metabolism of plants, and can improve its growth, development, physiological function, yields. REE can also restrain tumour and lung cancer,have the abilities of decreasing blood glucose and scavenging the free radicals by influencing immune activities and endocrine system of animals.However, REE cannot be efficiently untilized by the creatures under neutral conditions, because REE will form steady gel-deposit, which reduces its solubility. Rencent studies find that REE can combine with polysaccharides and form into polysaccharide-REE complexes, which can improve REE bioavailability. The complexes have efficient hydrolysis activities on the degradation of phosphodiester bond, especially to organophosphorus pesticides, while the structure of complexes and degradation mechanism of pesticides have not been reported.Several saccharide-REE complexes have been synthesized in this paper. In given conditions, the hydrolysis activities of different complexes are determined on pNPP2Na containing phosphodiester bond. The results show that hydrolysis activities of aldose-REE complexes are better than that of ketose-REE complexes, 6-C saccharide-REE complexes have higher hydrolysis activities than 5-C saccharide-REE complexes, and the hydrolysis activity of glucose-REE complex to pNPP2Na is the highest among the monsaccharide-REE complexes. Hydrolysis of polysaccharide-REE complexes to pNPP2Na shows that hydrolysis activities have correlation with content of aldose in polysaccharides. The complexes with polysaccharides mainly composed of aldose, especially 6-C saccharides, have conspicuous hydrolysis activities. Furthermore, degradation activities to phosphodiester bond are significantly related to the polymerization degree of polysaccharides, the higher the polymerization degree polysaccharide-REE更多还原