CHARACTERIZATION OF HUMIC ACIDS ISOLATED FROM ANTARCTIC SOILS

Humic acids isolated from Antarctic soils have been characterized by FTIR, C-13-NMR and elemental analysis; aminoacid content has been determined after hydrolysis with 6 N HCl. Nitrogen and hydrogen contents of HAs are very high, indicating that more proteinaceous material, covalently bound to the structures, has not undergone remarkable transformation during the humification processes. Moreover, the aliphatic carbon prevails on the aromatic one, owing to the nature of non-ligniferous material as precursor. With the progress of the humification process, obtained in temperate climatic conditions, the proteinaceous material decreases, as shown by the analysis of aminoacids, and the molecular weight of the humic compounds increases whereas aromatic carbon does not.