Study of marine carbon cycle based on stable carbon isotopic compositions of amino acids in marine sediments

点击翻译按钮获取中文摘要

This research aims to elucidate the dynamics and mechanism of organic matter preservation and degradation in marine sediments, using carbon isotopic compositions of amino acids as the main tool.In this year, I further modified the analytical method for isotope analyses of amino acids in marine sediment samples. I applied a new HPLC column, Hypercarb column, for the separation of amino acids. Finally, I achieved the successful analyses of individual hydrophilic amino acids in marine sediments, which cannot be achieved by the previous method. I confirmed the analyses by testing amino acid standards. This method also shows the potential for other isotope analyses, such as nitrogen isotope and radiocarbon, which would benefit future researches on environmental amino acids.Furthermore, I developed a new method for the isolation of individual D-amino acids in environmental samples using a chiral HPLC column, and confirmed the reliability of stable carbon and nitrogen isotope analyses. This method can be applied to study the D-amino acids in marine sediments, which can be potentially used as a microbial biomarker to study the sources and transformations of organic matter under the sea floor in the future.