| Autor: |
da Silva DA; Food Technology Department, Natural Science and Technology Center (CCNT), University of Pará State (UEPA), Belém 66050-540, PA, Brazil., Brasil DDSB; Chemical Engineering Faculty (FEQ), Institute of Technology (ITEC), Federal University of Pará (UFPA), Belém 66075-110, PA, Brazil., Cunha EJS; Chemical Engineering Faculty (FEQ), Institute of Technology (ITEC), Federal University of Pará (UFPA), Belém 66075-110, PA, Brazil., Aires GCM; Graduate Program in Food Science and Technology (PPGCTA), Institute of Technology (ITEC), Federal University of Pará (UFPA), Belém 66075-110, PA, Brazil., da Costa RA; Chemical Engineering Faculty (FEQ), Institute of Technology (ITEC), Federal University of Pará (UFPA), Belém 66075-110, PA, Brazil., do Rego JAR; Chemical Engineering Faculty (FEQ), Institute of Technology (ITEC), Federal University of Pará (UFPA), Belém 66075-110, PA, Brazil., Pena RDS; Graduate Program in Food Science and Technology (PPGCTA), Institute of Technology (ITEC), Federal University of Pará (UFPA), Belém 66075-110, PA, Brazil. |
| Abstrakt: |
A polysaccharide was isolated from the exudate of a buriti tree trunk ( Mauritia flexuosa ). The molecular structure, thermal stability, morphology, crystallinity, and elemental composition of the product were investigated through spectroscopic techniques, such as Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR 1 H and 13 C), and energy-dispersive X-ray spectroscopy (EDS); thermogravimetric analysis (TG), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and X-ray diffraction (XRD). In addition to NMR molecular modeling studies, were performed to confirm the 1 H and 13 C chemical shifts to Gal and Xyl conformers. Buriti tree gum (BG) is an arabinogalactan, containing Rha, Ara, Xyl, and Gal, and degrades almost completely (98.5%) at 550 °C and has a maximum degradation peak at 291.97 °C, with a mass loss of 56.33%. In the temperature range of 255-290 °C, the energy involved in the BG degradation process was approximately 17 J/g. DSC indicated a glass transition temperature of 27.2 °C for BG, which had an irregular and heterogeneous morphology, with smooth or crumbling scaly regions, demonstrating the amorphous nature of BG that was confirmed by the XRD standard. EDS revealed the presence of carbon and oxygen, as well as calcium, magnesium, aluminum, silicon, chlorine, and potassium, in the BG composition. |
