| In this paper, structure, chemical composition and physicochemical properties of
the novel polysaccharide Amuniacum gum (AMG) were assessed. The AMG had
12.21% moisture, 3.76% ash, 0.31% protein, 73.06% carbohydrate, 1.24% fat and
10% uronic acids. The elemental analysis indicated the absence of sulfur. The HPLC
demonstrated the presence of galactose and arabinose as dominant sugars. The
X-ray diffraction (XRD) pattern of the native gum indicated a semicrystalline structure.
Furthermore, gel permeation chromatography (GPC) showed that the average
molecular weight included 35 kDa. The Fourier transform infrared (FTIR) spectroscopy
showed the presence of hydroxyl, carboxyl and methyl groups. Moreover, 1H
and 13C NMR analysis demonstrated that AMG included a backbone of β-D-Galp
residues and was mainly branched through 4-O-methyl-α-D-glucopyranosyl units.
Results of thermogravimetric analysis (TGA) and differential scanning calorimetry
(DSC) indicated that the thermal decomposition of AMG occurred at nearly 278 °C.
In conclusion, these results highlight that the novel gum can be used in food and
pharmaceutical industries. |