Physicochemical Characterization of Exudate Gum from Neltuma flexuosa (ex Prosopis flexuosa)

Neltuma flexuosa exudate gum (NFEG) is a complex polysaccharide and a promising sustainable substitute for arabic gum, boasting an exceptional 92% extraction yield. Proximate analysis reveals an arabinogalactan–protein structure (89.9% carbohydrates, 3.2% protein) essential for its superior emulsifying and stabilizing properties. Composed mainly of galactose and arabinose, its random coil morphology ensures low viscosity at high concentrations, ideal for beverages. The presence of uronic acids (11.6%) provides a strong polyelectrolytic character, enhancing solubility and surface activity. Physicochemically, it mirrors arabic gum with an intrinsic viscosity of 19.90 cm3/g and thermal stability up to 237.4 °C. Structural analysis via FTIR and XRD confirms its amorphous polysaccharide nature and high chain flexibility. Furthermore, NFEG exhibits intrinsic bioactivity, including antioxidant properties confirmed by DPPH and reducing power assays. These dual functional properties present to NFEG as a high-value industrial hydrocolloid.