Distribution of inositol phosphate in the molecular size fractions of humic and fulvic acid fractions

Abstract

Abstract The characteristics of inositol phosphate in humic and fulvic acid fractions (HA and FA, respectively) extracted from a volcanic ash soil with resin and acetyl acetone were examined by Sephadex gel filtration. Both the HA and FA were fractionated into two parts according to their molecular size. Inositol phosphate was recognized in every fraction. The inositol phosphate was considered not to be in a free state but in a bound form with humic and nonhumic organic compounds. It was estimated that the organic phosphorus in the two fractions of HA and the higher molecular size fraction of FA consisted only of inositol phosphate, while that in the lower molecular size fraction of FA consisted of inositol phosphate and other organic phosphorus compounds.