Separation of soluble glycoproteins from sugarcane juice by capillary electrophoresis Original Research Article

Two different pools of glycoproteins, tentatively described as high and mid-molecular mass polymers, are currently separated by conventional gel filtration. Anion-exchange chromatography on DEAE-Sephadex A-60 discriminates between neutral or cationic, and anionic polymers composing both fractions. The occurrence of both cationic and anionic glycoproteins has been corroborated after separation by capillary electrophoresis. Total or partial digestion of the glycosidic moiety of these glycoproteins using β-1,2-fructofuranosidase reveals that cationic species from the mid molecular mass glycoproteins move to the neutral or anionic zone of the electropherogram whereas only one cationic form from high molecular mass polymers remains unchanged after enzymatic hydrolysis of the glycosidic moiety. This indicates that this moiety is able to modify the net charge of some of the mid-molecular mass glycoproteins whereas the net charge of cationic high molecular mass polymer can be due to the own protein moiety or, probably, to some polycationic polyamines bound on this moiety.