Analysis of starch-bound glucose 3-phosphate and glucose 6-phosphate using controlled acid treatment combined with high-performance anion-exchange chromatography

The products after controlled acid hydrolysis of starch, glucose (Glc), glucose 6-phosphate (Glc6P), glucose 3-phosphate (Glc3P), glucose-3 phosphate conversion products and inorganic phosphate (Pi) were separated using high-performance anion-exchange chromatography with pulsed amperometric detection (HPAC-PAD). Pi was derived from partial hydrolytic cleavage of the phospho-monoester bond in glucose 3-phosphate. The identity of the products was verified using P-31 nuclear magnetic resonance spectroscopy (P-31-NMR), The study demonstrates that Glc3P, despite of its susceptibility to acid catalysed dephosphorylation, can be liberated from starch together with Glc3P conversion products and Glc6P by controlled acid conversion enabling subsequent separation and analysis using HPAC. (C) 1998 Elsevier Science B.V. All rights reserved.