An exopolysaccharide, EPS-B108, was isolated from the fermented broth (with a yield of 11.3 g/L) of halotolerant Bacillus sp. SCU-E108 by ethanol precipitation, anion-exchange and gel-filtration chromatography, and well characterized by means of physical, chemical and spectral techniques. Data indicated that EPS-B108 was composed solely of fructose with a high molecular weight of 3.578 × 107 g/mol, and contained a β-(2→6)-linked d-Fruf backbone with a single β-d-Fruf at C-1 position. An irregular saccular- or cake-like shape was observed under the enlarged view. It showed no acute oral toxicity in mice, and had good thermal stability (242 °C), solubility in water (91.3%) and oil-holding capacity (1717.0%). Steady-shear flow and dynamical viscoelasticity of aqueous EPS-B108 solutions varied with the polymer concentration, shear rate and temperature, and were described by the Power-law model. Together, these findings support the further application of EPS-B108 as an alternative source of functional food additives and ingredients.
structure, exopolysaccharide, function, Rheology, Bacillus sp., levan
NCBI PubMed ID: 34237575Publication DOI: 10.1016/j.foodchem.2021.130496Journal NLM ID: 7702639Publisher: Elsevier Applied Science Publishers
Correspondence: yqtian@scu.edu.cn; pengbiyu@scu.edu.cn
Institutions: College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, PR China, Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu 610065, PR China
Methods: 13C NMR, 1H NMR, methylation, gel filtration, NMR-2D, GC-MS, X-ray, TLC, FTIR, composition analysis, HPSEC-MALLS, UV, HPAEC-PAD, statistical analysis, rheological study, SEM, emulsifying activity determination
Found