IMPROVED METHOD FOR THE ANALYSIS OF ALPHA-GALACTOSIDES IN PEA-SEEDS BY CAPILLARY ZONE ELECTROPHORESIS - COMPARISON WITH HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY TRIPLE-PULSED AMPEROMETRIC DETECTION

A capillary zone electrophoretic (CZE) method is described for the ana lysis of the raffinose family of oligosaccharides (RFO) in pea seeds. Extraction of RFO was carried out in 80% ethanol and the extract was p assed through a Sep-Pak C-18 cartridge. This proved to be an improveme nt on the currently accepted purification technique. High-quality elec trophoregrams were obtained which allowed the separation and quantitat ion of sucrose, raffinose, stachyose and verbascose. The CZE results w ere compared with those obtained by anion-exchange high-performance li quid chromatography coupled to a triple-pulsed amperometric detection (HPAC-PAD). The samples were obtained from four pea strains which were near-isogenic except for genes at the r and rb loci. A high degree of precision and reproducibility was obtained for the RFO compositions o f all the pea strains. No statistically significant differences (p les s than or equal to 0.05) were found between the two analytical techniq ues using paired Student-t tests.