Polyacrylamide gel electrophoresis of humic and fulvic acids after acid hydrolysis

Two soil humic acids (HA), a marine sediment HA, and a soil fulvic acid (FA ), were fractionated by polyacrylamide get electrophoresis in the presence of denaturing agents before and after 6N HCl hydrolysis. After acid hydroly sis, the intensity of the high molecular size (MS) fraction decreased consi derably in all HAs. On the other hand, a new high-MS fraction appeared in t he FA after hydrolysis. The electrophoretic data indicate that acid hydroly sis produced a transformation in the humic macromolecule, inducing either d epolymerization or condensation, depending on the nature of the humic fract ion. Therefore, the advantages and disadvantages of using acid hydrolysis s hould be carefully considered before this treatment is carried out.