Studies on acacia exudate gums. Part V. Structural features of Acacia seyal

The distribution of the protein is different between the various components which constitute the gums. In A. senegal the protein is mainly located in association with the high molecular weight component (AGP-peak 1). Enzyme hydrolysis points to two components being associated with the high molecular weight material in A. seyal, only one of which is degraded by the enzyme pronase. In hydrophobic fractionation studies, a protein rich component of extremely high molecular weight (Fraction 3) was found in A. seyal but not in A. senegal. In size fractionation this would co-elute with the main component, which is further evidence for the presence of the two different high molecular weight components in A. seyal, unlike A. senegal. The adsorption of these high molecular weight protein fractions of A. seyal onto an oil droplet was tested and found not to be a highly efficient emulsifying component. Structurally, while A. seyal may have the same core structural linkages as A. senegal, the degree of branching is greater, with the protein distributed differently.