Preparation, characterization and functional properties of a novel exopolysaccharide produced by the halophilic strain Halomonas saliphila LCB169T

A novel exopolysaccharide, designated hsEPS, was successfully prepared from the high-salt-fermented broth of a novel species Halomonas saliphila LCB169(T) by ethanol precipitation, anion-exchange and gel-filtration chromatography, and its structure was well-characterized by means of chemical and spectral analyses. Results showed that hsEPS was primarily composed of mannose and glucose with a relative weight-average molecular weight of 5.133 x 10(4)g/mol. It was deduced that the major backbone contained (1 -> 2)-linked alpha-D-Manp and (1 -> 6)-linked alpha-D-Manp with branches substituted at C-2 by T-alpha-D-Manp and at C-6 by the fragment of T-alpha-D-Manp-(1 -> 2)-alpha-D-Manp-(1 ->. A sheet-like structure was observed under high magnification. The water solubility index, water holding capacity, oil holding capacity and foaming capacity of hsEPS were 98.0, 19.3,1386.7 and 82.2%, respectively. It also exhibited outstanding emulsifying activity against all tested edible oils. Together, the resulted data indicated that hsEPS might serve as an active ingredient in food, cosmetics and detergents. (C) 2020 Published by Elsevier B.V.