基于X射线荧光成像技术研究海洋微藻对重金属吸收的机理

项目名称： 基于X射线荧光成像技术研究海洋微藻对重金属吸收的机理

项目编号： No.41506129

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 天文学、地球科学

项目作者： 姜玥璐

作者单位： 清华大学

项目金额： 22万元

中文摘要： 工业化与城市化快速发展大量引入的重金属元素除了抑制水生生物生长，在水生生物体内富集，还对初级生产力和生态系统结构产生深远复杂影响，海洋污染已成为全球性环境热点问题。本项目将针对多种微量元素（Mn、Ni、Cu、Cd和Zn），单一或复合存在时对海洋微藻细胞生理、光合作用、生物化学组成等主要生理指标的影响，完善复合重金属联合作用理论；利用X射线荧光成像技术，对微藻细胞吸附金属元素机理和分布动力学进行高解析度分析，研究微量元素在胞外沉积部位，在细胞壁上与功能基团的吸附和状态，及对其在胞内分布、输送及富集进行研究；研究重金属元素对微藻细胞内脂类含量和构成的影响，探讨吸附、富集重金属元素同时生产微藻燃料的前景。现阶段，关于重金属污染物对海洋微藻生物效应及利用微藻除污或开发新能源已有不少学者进行了研究，但藻细胞吸附富集重金属元素机理及优化条件仍需更多研究，这将为进一步探讨该研究在工业中应用提供理论依据。

中文关键词： 海洋微藻；微量金属元素；X射线荧光成像系统；吸附机理；微藻油脂

英文摘要： Water pollution has a long history along with the existence of mankind. It seems very convenient to dispose all kinds of liquid and solid wastes into aquatic systems. Nowadays, wastewater released from industrial and municipal sources is posing serious challenges to the aquatic environments, and becomes a global problem need to be solved in sustainable ways. The released wastewater rich in organic compounds and inorganic chemicals such as nitrates and phosphates can introduce eutrophication, and metals can inhibit the phytoplankton growth, metabolic activity, toxic to aquatic organisms and human being through bio-accumulation. Microalgae have been proved in many studies that have the ability to absorb metals from environment. .In this study, we will investigate the effects of Mn, Ni, Cu, Cd and Zn, single or combined, on the growth, photosynthesis performance, and biochemical compositions. By using high resolution X-ray fluorescent image system, investigate the mechanism of heavy metals uptake and accumulation by microalgae and the dynamic of cellular metal distribution, demonstrate the extracellular trace metals deposition location, their status after bound to functional groups on cell wall, and intracellular distribution, transportation and accumulation. Additionally, by studying the effects of metals on microalgal cellular biochemical composition changes, especially lipid production, will explore the potential of lowering the cost of microalgal heavy metals bioremediation, which is still not economically feasible yet..There have extensive studies of micoralgae used in bio-monitoring or bioremediation purposes, but the mechanism of the trace metals uptake, transportation and accumulation with and within the microalgal cells is still unclear. Meanwhile, the cellular metal allocation related to different cellular metabolic processes, such as photosynthesis performance, nutrient incorporation, and antioxidative defenses, must be better understood. This work will lead to effective use and accelerate the development of microalgae as effective metal biosorbents as well as biodiesel producers.

英文关键词： marine microalgae;trace metals; X-ray fluorescent image system;trace metals deposition mechanisms;microalgal lipid