Humic acids in bottom sediments of the Western Pacific

Elemental composition, functional groups, and molecular mass distribution were determined in humic acids from the Western Pacific abyssal and coastal bottom sediments. Humic acid structure was studied by oxidative degradation with alkaline nitrobenzene and potassium permanganate, p-coumaric, guaiacilic, and syringilic structural units typical for lignin of terrestrial plants were identified in humic acids by chromatographic analysis of oxidation products. Polysubstituted and polycondensed aromatic systems with minor proportion of aliphatic structures were basic structural units of humic acids in abyssal sediments.针对西太平洋深渊与近岸海底沉积物中的腐殖酸（humic acid），本研究测定了其元素组成、官能团及分子质量分布。采用碱性硝基苯氧化降解与高锰酸钾氧化降解两种手段，对腐殖酸的结构进行了分析；通过对氧化产物的色谱分析，在腐殖酸中鉴定出陆地植物木质素所特有的对香豆素基、愈创木基及紫丁香基结构单元。深渊沉积物中腐殖酸的基本结构单元为多取代、多缩合芳香体系，仅含有少量脂肪族结构。