Preparative Fractionation Analysis of Acacia polyacantha Gum Using Acetone as a Solvent

Abstract

Five authentic Acacia polyacantha whole gum samples were collected as natural exudates and five acetone fractions were obtained. Analysis of the whole gum samples and the fractions were carried out t for nitrogen (protein), specific rotation, intrinsic viscosity, pH, equivalent weight, uronic acid content, refractive index and average molecular weight. Results of refractive index for the whole samples and the fractions were found to share the same value (1.3337). Significant differences were obtained between the values of these parameters for the whole gum samples as well as the fractions and it is also among the fractions themselves. In particular fractions 1,2,3,4and 5 showed nitrogen content of 0.32%, 0.35%, 0.40%, 0.39%and0.37% and protein content of (2.11%,2.31%,2.64%, 2.57% and2.44%) respectively. The mean values of specific optical rotation of the fractions was found-13.5 0, -14.50, -15.0 0,-16.00 and -14.50 respectively. The average molecular weight of the fractions gave 2.669x105, 2.669X105, 2.714X105, 2.339X105 and 2.754X105 respectively. The statistical analysis showed significant differences (P ≤ 0.05) for some parameters such as, intrinsic viscosity, pH and the average molecular weight. These data confirms the heterogeneity of Acacia polyacantha gum, and their fractions.