title: Structural and physicochemical characteristics of a novel water-soluble gum from Lallemantia royleana seed.
abstract: In this study, the structural information (monosaccharide compositions, molecular weight parameters & FTIR analysis), chemical composition (moisture, protein, ash, carbohydrate & uronic acids), rheological properties, and surface activity of Lallemantia royleana seeds mucilage (BSG) were determined. The results showed BSG contains 8.51% (w.b.) moisture, 8.24% (d.b.) ash, 2.71% (d.b.) protein, 75.87% (d.b.) carbohydrate and 20.33% (d.b.) uronic acids. Monosaccharide analysis revealed the presence of arabinose (37.88%), galactose (33.54%), rhamnose (18.44%), xylose (6.02%) and glucose (4.11%) in the BSG polysaccharide. Although BSG had similar molecular weight (1.294×10(6) Da) compared to most seed gums, the intrinsic viscosity (23.06 dL/g) and gyration radius (104.84 nm) were higher. The BSG exhibited a strong shear-thinning behavior (n<0.29) over the shear rate range of 0.01 to 1000 s(-1). Flow behavior data was correlated with different time-independent models, which provided a good description of BSG rheological properties. Dynamic mechanical spectra demonstrated BSG is a typical of weak gel, which its rheological parameters were superior to those of many commercial gums. The FTIR spectra of the BSG polymer showed the presence of carboxyl groups, which may serve as binding sites for ions. BSG exhibited the ability to reduce the surface tension of water at concentrations lower than 0.75%.
authors.affiliation: Food Hydrocolloids Research Center, Department of Food Science and Technology, Ferdowsi University of Mashhad (FUM), PO Box: 91775-1163, Mashhad, Iran. Electronic address: s.razavi@um.ac.ir.
authors.forename: Seyed Mohammad Ali
authors.initials: SM
authors.lastname: Razavi
authors.affiliation: Guelph Food Research Center, Agriculture and Agri-Food Canada, Guelph, ON, Canada N1G 5C9.
authors.forename: Steve W
authors.initials: SW
authors.lastname: Cui
authors.affiliation: Guelph Food Research Center, Agriculture and Agri-Food Canada, Guelph, ON, Canada N1G 5C9.
authors.forename: Huihuang
authors.initials: H
authors.lastname: Ding
mesh_terms: D001665:Binding Sites; D005690:Galactose / Q000737:chemistry; D005947:Glucose / Q000737:chemistry; D019686:Lamiaceae / Q000737:chemistry*; D008970:Molecular Weight; D009005:Monosaccharides / Q000737:chemistry; D053149:Plant Gums / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry; D012210:Rhamnose / Q000737:chemistry; D012212:Rheology; D012639:Seeds / Q000737:chemistry*; D033081:Shear Strength; D014574:Uronic Acids / Q000737:chemistry; D014783:Viscosity; D014867:Water / Q000737:chemistry*; D014994:Xylose / Q000737:chemistry
chemical_list: D009005:Monosaccharides; D053149:Plant Gums; D011134:Polysaccharides; D014574:Uronic Acids; D014867:Water; D014994:Xylose; D005947:Glucose; D012210:Rhamnose; D005690:Galactose
keywords: Composition; Conformation; Light scattering; Rheology; Seed mucilage; Structure