Department of Agriculture, Calcutta University, Calcutta
* Present address: Department of Macromolecules, Indian Association for the Cultivation of Science, Calcutta-32
** National Commission on Agriculture, Vigyan Bhavan Annexe, New Delhi.
Chromatographically separated fractions as well as the crude humic acids obtained by successive extractions from the humin fraction of soil were subjected to acid hydrolysis. In the hydrolysates, sugars, amino acids and phenols were detected. Presence of minute amounts of sugar in the hydrolysate suggests that it might not be an essential constituent of humic acids. In the alkaline cupric oxide oxidation products of humic acids, amino acids and phenols were detected. The latter occur progressively in lesser amounts in the successive extractions.
Humic acid, humin fraction of soil
