FRACTIONATION AND CHARACTERIZATION OF GUM-ARABIC SAMPLES FROM VARIOUSAFRICAN COUNTRIES

Four gum arabic samples obtained from Various African countries (Sudan , Chad and Senegal) were separated into three or four fractions by hyd rophobic interaction chromatography on Phenyl Sepharose CL-4B. The mol ecular mass distribution of the fractions was monitored using gel perm eation chromatography on a Superose 6 column and indicated that each w as polydisperse confirming the extreme heterogeneous nature of the gum . The fractions were characterized using various chemical and physicoc hemical techniques. For all four gum samples the major fraction which represented >90 wt% of the total yield was found to be low in protein (<2%). The other minor fractions (similar to 10 wt% of the total) were found to have higher proportions of protein (similar to 10-60%). Desp ite the differences in their geographical origin, the molecular mass d istribution, specific rotation and sugar composition of the parent gum s and their equivalent fractions did not differ significantly.