【作者】 郭丽；

【导师】 陈宏丽；

【作者基本信息】 兰州大学 ， 分析化学， 2009， 硕士

【摘要】 尼泊金酯类物质是一类重要的防腐剂,已被广泛用于食品、饮料、化妆品、医药等许多领域。在食品中使用防腐剂可以防止食品霉腐,具有效果显著、方法简便、设备投资少等优点,但使用时必须把防腐剂的安全性放在首位,从经济、毒性等方面考虑,严格限制用量。人血清白蛋白(Human serum albumin,HSA)是血浆中含量最丰富的蛋白质,具有很多生理学上的功能,在体内起着存储和转运作用。HSA与尼泊金酯类防腐剂的相互作用会影响防腐剂在体内的分布、代谢及排泄方式,因此,HSA与尼泊金酯相互作用的研究可为科学、合理的使用此类防腐剂提供重要的理论依据。基于此,本论文在总结前人工作的基础上,综合各种光谱实验技术及化学信息学,从使用尼泊金酯类防腐剂的安全性出发,从分子水平的角度研究了此类防腐剂与人血清白蛋白的相互作用。本论文进行了以下几方面的创新性研究:(1)首次选择了尼泊金酯类防腐剂(对羟基苯甲酸丙酯)作为研究对象,研究其与人血清白蛋白的相互作用;(2)利用荧光光谱、紫外光谱、圆二色谱和傅里叶变换红外光谱考察了对羟基苯甲酸丙酯对HSA二级结构的影响;用计算机分子模拟方法进行了对羟基苯甲酸丙酯与HSA的对接,获得与实验基本一致的结果。论文共分为三章:第一章:简要介绍了尼泊金酯类防腐剂的使用现状及人血清白蛋白的结构、功能和性质;综述了有机小分子物质与蛋白质相互作用的研究方法、作用力类型及研究进展。第二章:用荧光光谱法、紫外光谱法、圆二色谱法、红外光谱法及分子模拟技术对对羟基苯甲酸丙酯和人血清白蛋白的相互作用进行了详细的研究。结果表明,对羟基苯甲酸丙酯与蛋白质之间有一定的结合作用,结合后蛋白质的二级结构发生了轻微的改变。分子模拟结果表明对羟基苯甲酸丙酯和蛋白质的结合区域位于蛋白质的亚结构域ⅡA中,主要通过氢键作用结合,这和光谱实验研究所得到的结果是基本一致的。第三章:用组合法合成HCuNVAsPWO杂多化合物催化剂,并对催化剂进行表征,探讨了Cu、As含量及不同焙烧温度对催化剂催化性能的影响。结果表明,Cu和As的引入可大大提高催化剂的活性和乙醛的收率;焙烧温度为350℃,催化剂的活性最佳。更多还原

【Abstract】 Nipagin ester as a kind of important preservatives has been widely used in food, beverage, cosmetic, medicine and many other areas. The use of preservative in food has many advantages, such as simple method, less investment in equipment, and so on. But it is necessary to limit the dosage of preservative from economic, toxic and other considerations. Human serum albumin (HSA) has a high concentration in blood plasma and has many physiological functions, it can realize transport and distribution of many small molecules and metabolites in the plasma. Preservative-HSA interaction should have a great influence upon the distribution of the preservative in the body, upon their patterns of metabolism and excretion, investigating the binding mechanism of preservative binding to HSA can provide an importance theoretical base on the scientific and reasonable use of preservative. On the basis of the previous researches, the following major innovative works were carried out in this dissertation:(1) For the first time, the interaction between nipagin esters preservative (propylparaben) and human serum albumin was investigated;(2) The effects of propylparaben on HSA second structure were investigated by fluorescence spectroscopy, ultraviolet spectrum, FT-IR and circular dichroism techniques. The computational modeling method was used to study the interaction between propylparaben and HSA, and the results were in consistent with the experimental results.This dissertation consists of three chapters:Chapter 1: The structures, functions and natures of HSA were briefly introduced. The methods、types of interaction force and evolvement about the interaction of different kind of small ligands with protein were reviewed in detail. Chapter 2: The binding of propylparaben to HSA has been investigated for the first time by the fluorescence method, ultraviolet spectrum, FT-TR, CD spectroscopy and molecular modeling. The results have clearly indicated that propylparaben can bind tightly to HSA with changing slightly its molecular conformation. Meanwhile, from the results of binding mode and molecular modeling, it can be revealed that propylparaben has bound within the subdomain IIA of HSA mainly by the hydrogen bond.Chapter 3: The HCuNVAsPWO heteropoly compounds catalysts were prepared by Combination method and characterized by IR spectrum technique. The effects of the contents of Cu and As and the calcining temperature on the activity of catalysts were studied. The resuhs show that the additions of Cu and As are very important for increasing the activity and the yield of the acetaldehyde. The catalysts calcined at 350℃have the highest activity.更多还原