Rheological characterization of the exopolysaccharide produced by Alteromonas macleodii Mo 169.
Int J Biol Macromol
; 227: 619-629, 2023 Feb 01.
Article
em En
| MEDLINE
| ID: mdl-36539173
ABSTRACT
Rheology modifiers are essential additives in numerous products in a variety of industries. Due to environmental awareness, consumer-oriented industries are interested in novel natural rheological agents that can replace synthetic chemicals. In this study, the chemical composition and rheological properties of a novel exopolysaccharide (EPS) produced by Alteromonas macleodii Mo 169 were investigated. It was mainly composed of uronic acids (50 mol%) and total carbohydrates were 17 % sulfated. The EPS viscosity increased with concentration, and a non-Newtonian shear thinning behavior was found for concentrations above 0.1 wt%. The elastic and viscous moduli indicated a weak gel-like structure above 0.4 wt%. It maintained its shear thinning behavior and viscoelastic properties in the presence of NaCl and CaCl2 for pH range 5-7 and temperatures up to 55 °C. Though the apparent viscosity decreased at pH 3 and 9 and temperatures above 65 °C, the shear thinning behavior was retained. The viscous and viscoelastic properties were recovered after heating (95 °C) and cooling (0 °C), indicating a good thermal stability and recoverability. After high shear force, the solution recovered original rheological properties within few seconds, demonstrating self-healing properties.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cloreto de Sódio
Idioma:
En
Revista:
Int J Biol Macromol
Ano de publicação:
2023
Tipo de documento:
Article