| Popis: |
The objective of this work was to study humic acids (HAs), and their fractions obtained by coupling size exclusion chromatography-polyacrylamide gel electrophoresis, from arctic soil, podzolic soil, grey forest soil, chernozem and red soil, in respect to their amino acids composition and content. The fractions had exactly defined molecular size (MS) and electrophoretic mobilities (EM). While HAs and fractions had remarkably similar amino acids compositions, they differed greatly in amino acids contents. The highest quantity of amino acids was found in high MS fractions (11.5–21.7%). Amino acids content essentially decreased (to 2.1–5.5%) with the increasing of elution volumes and EM of HAs fractions, independently of HA sources. Separation of HA into less complex fractions with defined molecular and electrophoretic entities, which differ by their content of amino acids, could be of great value for studies on physical-chemical structures of HA and its genesis in soil. |
Full Text from ScienceDirect