Identification and Significance of Long Chain Fatty Acid Methyl Ester in the Surface Sediment of Taihu Lake

在太湖表层沉积物中检测出丰度较高的一系列长链脂肪酸甲酯化合物,采用标准图谱与质谱解析相结合的方法进行鉴定.长链脂肪酸甲酯化合物有类似正构烷烃的分布型式,碳数分布范围为C14-C34,主峰碳为C16,具有明显的偶碳优势对太湖沉积物中长链脂肪酸甲酯化合物的来源、存在的地球化学环境等进行了讨论,初步认为长链脂肪酸甲酯化合物是反映湖泊沉积环境的重要有机标记化合物之一;The aromatic hydrocarbon fraction of the surface sediment in the west and east part of Taihu Lake was analyzed by GC-MS.As a result, a series of long chain falty acid methyl esters was first found. Distribution of the carbon number of fatty acid methyl esters in the samples was from C14 to C34 maximizing at C16 with a strong even to odd carbon preference.Their mass spectrum characteristics are that base peaks were M/Z 74, 87 and characteristic ions were M/Z 143, 199, M+, M-43+.These ion existence was confirmed by fragmenting analyses of fatty acid methy esters.The origin of the long chain fatty acid methy esters in the sediment of Taihu Lake was also studied, which may be related to biochemical process. The result showed that the long chain fatly acid methyl esters was probably an important biological marker to study the acidity of the lake sediment.