title: Structural and thermal characterization of galactomannans from genus Gleditsia seeds as potential food gum substitutes.
abstract: BACKGROUND
  Seed galactomannans are preferred hydrocolloids since they are comparatively cheap, non-toxic, eco-friendly and non-polluting during production and application. Galactomannans from seeds of three species of Gleditsia, namely G. sinensis, G. microphylla and G. melanacantha, were characterized in terms of structural and thermal properties.
  
  
  RESULTS
  Gleditsia polysaccharides were characterized using both chemical and chromatographic methods, as well as Fourier transform infrared, (1) H nuclear magnetic resonance (NMR) and (13) C NMR spectroscopy, and it was shown that they consist of D-mannopyranose and D-galactopyranose residues. The mannose/galactose (M/G) ratio of galactomannans was 3.25, 3.31 and 2.30, respectively. It was also found that these polysaccharides differ from one another in values of M(w) , M(n) and polydispersity. X-ray diffraction confirmed the amorphous nature of Gleditsia galactomannans, although G. sinensis galactomannan showed a high crystallinity. Thermal analysis of the galactomannans by differential scanning calorimetry illustrated that their endothermic peaks ranged from 290 to 320 °C.
  
  
  CONCLUSIONS
  Gleditsia polysaccharides are neutral galactomannans. The higher value of M/G ratio from G. sinensis and G. microphylla indicates that their gums offer an excellent alternative for locus bean gum.
authors.affiliation: Department of Chemistry and Chemical Engineering, Beijing Forestry University, Beijing 100083, China. jiangjx2004@hotmail.com
authors.forename: Jian-Xin
authors.initials: JX
authors.lastname: Jiang
authors.forename: Hong-Lei
authors.initials: HL
authors.lastname: Jian
authors.forename: Carrasco
authors.initials: C
authors.lastname: Cristhian
authors.forename: Wei-Ming
authors.initials: WM
authors.lastname: Zhang
authors.forename: Run-Cang
authors.initials: RC
authors.lastname: Sun
mesh_terms: D003102:Colloids / Q000737:chemistry; D005690:Galactose / Q000032:analysis / Q000031:analogs & derivatives; D031501:Gleditsia / Q000737:chemistry*; D008351:Mannans / Q000737:chemistry*; D008358:Mannose / Q000032:analysis; D015394:Molecular Structure; D053149:Plant Gums / Q000737:chemistry*; D012639:Seeds / Q000737:chemistry*; D013045:Species Specificity
chemical_list: D003102:Colloids; D008351:Mannans; D053149:Plant Gums; C012990:galactomannan; D008358:Mannose; D005690:Galactose