【作者】 向润清；

【导师】 蒋春跃；

【作者基本信息】 浙江工业大学 ， 化学工程， 2011， 硕士

【摘要】 了解氨基酸在海水中的分布不仅对海洋中碳、氮的地球化学循环过程有着重要意义,还可以探索蛋白质/氨基酸在海洋生物食物链中的循环,从而阐明沉积物中蛋白质物质的来源,为进一步研究海相沉积物中氨基酸与无机矿床成因关系等提供必要的基础资料。海水氨基酸最常用的检测方法是利用氨基酸自动分析仪自动分析,检测时要求样品必须是低离子浓度,因此在进行检测分析之前必须对海水样品进行脱盐、富集等预处理。该过程耗时又费力,且放置和处理时间过长也会因样品中微生物消耗等原因造成结果可信度的下降。荧光法因其无需对海水样品进行预处理等过程而广泛地应用于海水荧光性物质的研究。荧光物质的荧光效应不仅与其自身的结构有关,而且与物质所处的环境有关,如在不同的静水压力下,荧光性物质色氨酸的荧光光谱将发生显著变化;离子种类和浓度的不同也将影响到色基酸的荧光光谱。酪氨酸作为三种天然荧光氨基酸之一,是合成儿茶酚胺类神经递质——多巴胺、肾上腺素和去甲肾上腺素的氨基酸前体物,因此酪氨酸对于提高心理和作业效率的营养干预措施正在日益受到重视。因此,本文在综述了海洋氨基酸的研究概况和高压荧光法基本原理的基础上,以酪氨酸为研究对象,在自建在线高压荧光检测平台上,考察了海水pH值,常压至60 MPa条件下,压力对酪氨酸荧光光谱的影响,同时研究了在不同离子种类、浓度条件下,压力对酪氨酸荧光光谱的影响。研究结果表明:（1）酪氨酸水溶液荧光光谱最大发射光在本实验的条件下均无变化;（2）酪氨酸水溶液荧光强度随压力的增加而增强;（3）常压下,K⁺、Mg²⁺对酪氨酸水溶液荧光强度无影响,而Ni²⁺、Cu²⁺对酪氨酸水溶液荧光强度具有明显的猝灭作用,且浓度越大,猝灭越强;（4）在Ni²⁺、Cu²⁺存在下,压力对酪氨酸水溶液荧光强度的增敏作用随Ni²⁺、Cu²⁺浓度的增加而增强。上述结果在将酪氨酸作为外源引入或内源性探针在探索蛋白质的构象变化以及在线检测海洋中的溶解态蛋白质及其氨基酸组分等方面具有一定的参考价值;也为探索深海热液口生物耐高金属离子浓度的机制提出一种新的思路。?更多还原

【Abstract】 Study of the distribution of amino acids in seawater not only has great significance on the marine carbon and nitrogen in the geochemical cycle but also can explore the circulation of protein（amino acids） in marine food chain and clarify the source of protein in sediments.Detections of marine amino acids most commonly used are automatic analysis of amino acid analyzer, which the sample must be lower concentration. Therefore, the sample must be desalinated and enriched before detection, and this preprocessing are time-consuming and laborious. Fluorescence widely used in fluorescent substances in marine because of no pretreatment process. The fluorescence of fluorescent substances is not only related to the structure itself, and it also related to their environment, such as at different hydrostatic pressure the fluorescence spectrum of amino acid will be a significant change, different ion type and concentration will also affect fluorescence spectroscopy.As one of three natural fluorescent amino acid, tyrosine（Tyr） is the precursor of synthesis catecholamine neurotransmitters-dopamine, epinephrine and norepinephrine. Therefore, Tyr became more and more important in measures of nutritional interventions for improving the psychological and operational efficiency. So, in this paper, on the basis of reviews on the research of marine amino acids and basic principle high-pressure fluorescence, we studied the effect of pressure on fluorescence Spectrum of Tyr aqueous solution and Tyr in different concentrations of K+、Mg²⁺、Ni²⁺、Cu²⁺ on the conditions of pH of seawater and the pressure from atmospheric pressure to 60 MPa. Results showed:（1） Theλmax of Tyr aqueous solution had no change in our experiment conditions.（2） The fluorescence intensity of Tyr aqueous solution enhanced with increased hydrostatic pressure.（3） At atmospheric pressure, the fluorescence intensities of Tyr aqueous solution were constant in the presences of K+、Mg²⁺ but quenched obviously in the presences of Ni²⁺、Cu²⁺ where the quenching became stronger when the concentration increased.（4） The effect of pressure on the fluorescence intensity of Tyr aqueous solution was different in the presences of various Ni²⁺、Cu²⁺ concentrations, When Ni²⁺、Cu²⁺ concentration was lower, the fluorescence intensity increased relatively smaller and vice versa the fluorescence intensity increased relatively higher. The study of tryptophan fluorescence provide some reference value for the on-line research of the ocean dissolved protein and amino acids and the study of Tyrosine as exogenous or endogenous probes to explore protein conformational changes and also provide a new idea on exploring the mechanisms of deep-sea hydrothermal vents community resistant to high metal ion concentration.更多还原