Variation in Physicochemical Properties of Gum from Acacia seyal var. seyal

Abstract

Physicochemical properties of Acacia seyal var. seyal gum were studied for two samples, sample A, clear nodules, pale yellow color and sample B, deep orange mass. The samples were collected from the same tree from Al Gadarif state. The methods include: pH, moisture content, ash content, specific optical rotation, nitrogen and protein content, sugar composition, intrinsic viscosity, equivalent weight, total uronic acid percentage, and cationic composition for the two samples A and B. Standard characterization methods were used to obtain the values of moisture content, ash content, pH, and specific optical rotation. The cationic composition study using inductively coupled plasma (ICP) technique, while the sugar composition study using high performance liquid chromatography (HPLC) technique. The results show that: pH of sample A is 4.97 and for sample B is 4.88, ash content is 2.65% for sample A and 3.11% for sample B, the moisture content is 8.33% for sample A and 3.5% for sample B, the specific optical rotation is +57.0 deg g-1 cm2 for sample A and +83.3 deg g-1 cm2 for sample B, acid equivalent weight is 1538 for sample A and 1229 for sample B, the total uronic acid percentage is 12.6% for sample A and 15.8% for sample B, the intrinsic viscosity is 9.2 ml g-1 for sample A and 15.7 ml g-1 for sample B , the sugar composition was found to be as follows, rhamnose is 1.23% for A and 0.56% for B, arabanose is 37.46% for A and 43.81% for B, galactose is 20.47% for A and 23.34% for B, the results of nitrogen content is 0.151% for A and 0.159% for B, the protein content is 0.997% for A and 1.050% for B, the cationic composition of Acacia seyal var. seyal samples was determined and the result for sample A show that calcium is the most abundant (7076 ppm) followed by potassium (4776 ppm), magnesium (1603 ppm), sodium (41.23 ppm), lead , iron , zinc, and chromium are traces, while the cationic composition result for sample B is calcium (7977 ppm), potassium (3713 ppm), magnesium (792.6 ppm), sodium (35.68 ppm), lead , iron , zinc, and chromium are traces.