Analytical studies on the gum exudate from Anogeissus leiocarpus

Anogeissus leiocarpus gum samples were collected as natural exudate nodules, from three different location. Physicochemical properties of gum samples were studied. results showed significant differences within each location in most parameters studied except refractive index value which was found to be constant in all samples. The effect of location on the properties of gum samples was also studied and the analysis of variance showed insignificant differences (P≤0.05) in all properties studied except in ash content. Inter nodule variations of gum from two different location were studied individually. Results showed significant differences for each parameter studied except for the refractive index value. The properties studied of all gum samples were as follows: 9.2% moisture, 3.4% ash, 0.72% nitrogen, 4.74% protein, -35.5 specific rotation, 1.68 relative viscosity, 4.2 pH, 1.334 refractive index, 14.3 uronic acid, 0.44% reducing sugar, 1336.0 equivalent weight and 0.68% tannin content. UV absorption spectra of gum samples and gum nodules were determined. Cationic composition of gum samples was also determined and the results showed that (Mg) has highest value in all samples studied followed by Fe, Na, K, Ca, Zn and trace amount of Mn, Co, Ni, Cd and Pb. The water holding capacity was found to be 65.5% and emulsifying stability was found to be 1.008. The component sugars of gum were examined by different methods followed by qualitative and quantitative analysis. Analysis of hydrolysate crude gum sample by HPLC show L-rhamnose (6.82), L-arabinose (48.08), D-galactose (11.26) and two unknown oligosaccharides having values (0.22 and 32.61). Some physicochemical properties were studied. Results showed significant differences in nitrogen and protein contents, specific rotation, relative viscosity, equivalent weight and pH of fractions, where as insignificant differences were observed in uronic acid content and refractive index values