The use of gas‐liquid chromatography to determine the proportions of inositol isomers present as pentakis‐ and hexakisphosphates in alkaline extracts of soils

A method for determining the relative proportions of inositol isomers present in soil as their pentakis‐ and hexakisphosphate derivatives (IP5 + IP6) is presented. The method involves determination of the isomers as their hexakis‐O‐acetyl derivatives by gas‐liquid chromatography. The only isomers detected in extracts of 4 soils were chiro‐inositol, neo‐inositol, myo‐inositol and soyllo‐to‐inositol. Little variation in the relative proportions of the isomers was found between the 4 soils but the relative proportion of the neo‐isomer was considerably greater than previously published estimates. The method also makes possible the estimation of the (IP5 + IP6) fraction, using anion‐exchange chromatography on a aliquot of the extract.