An enzymatically produced soluble -glucan fiber composition is provided suitable for use as a digestion resistant fiber in food and feed applications. The soluble -glucan fiber composition can be blended with one or more additional food ingredients to produce fiber-containing compositions. Methods for the production and use of compositions comprising the soluble -glucan fiber are also provided.

Compositions are disclosed herein comprising a graft copolymer that comprises: (i) a backbone comprising dextran that has been modified with about 1%-25% alpha-1,2 branches, and (ii) one or more alpha-1,3-glucan side chains comprising at least about 50% alpha-1,3 glycosidic linkages. Further disclosed are reactions for producing such graft copolymers, as well as their use in derivatives, films and various other applications.

Compositions are disclosed herein comprising a graft copolymer that comprises: (i) a backbone comprising dextran that has been modified with about 1%-25% alpha-1,2 branches, and (ii) one or more alpha-1,3-glucan side chains comprising at least about 50% alpha-1,3 glycosidic linkages. Further disclosed are reactions for producing such graft copolymers, as well as their use in derivatives, films and various other applications.

The invention relates to: a protein having dextran-saccharase activity and the sequence SEQ ID NO: 1 for an amino acid sequence; a protein having dextran-saccharase activity and the sequence SEQ ID NO: 2 for an amino acid sequence; a complex containing a substrate and a protein with dextran-saccharase activity a method for synthesizing dextrans; and dextrans. The invention also relates to a method for synthesizing gluco-oligosaccharides and gluco-conjugates and to the resulting products.

The invention relates to: a protein having dextran-saccharase activity and the sequence SEQ ID NO: 1 for an amino acid sequence; a protein having dextran-saccharase activity and the sequence SEQ ID NO: 2 for an amino acid sequence; a complex containing a substrate and a protein with dextran-saccharase activity a method for synthesizing dextrans; and dextrans. The invention also relates to a method for synthesizing gluco-oligosaccharides and gluco-conjugates and to the resulting products.

The subject matter of the invention is dextrans which have between 95% and 99% of -1,6 glucosidic bonds, a weight-average molar mass M.sub.w at least equal to 0.710.sup.9 g.mol.sup.1, and a dispersity index D of between 1.3 and 3. The invention also relates to a dextran saccharase which makes it possible to produce such dextrans, and to a method for producing said dextrans.

The subject matter of the invention is dextrans which have between 95% and 99% of -1,6 glucosidic bonds, a weight-average molar mass M.sub.w at least equal to 0.710.sup.9 g.mol.sup.1, and a dispersity index D of between 1.3 and 3. The invention also relates to a dextran saccharase which makes it possible to produce such dextrans, and to a method for producing said dextrans.

Compositions are disclosed herein comprising a graft copolymer having (i) a backbone comprising dextran with a molecular weight of at least about 100000 Daltons, and poly alpha-1,3-glucan side chains comprising at least about 95% alpha-1,3-glucosidic linkages. Further disclosed are reactions for producing such graft copolymers, as well as their use in absorbent materials.

Compositions are disclosed herein comprising a graft copolymer having (i) a backbone comprising dextran with a molecular weight of at least about 100000 Daltons, and poly alpha-1,3-glucan side chains comprising at least about 95% alpha-1,3-glucosidic linkages. Further disclosed are reactions for producing such graft copolymers, as well as their use in absorbent materials.

Compositions are disclosed herein comprising dextran that comprises (i) 87-93 wt % glucose linked at positions 1 and 6; (ii) 0.1-1.2 wt % glucose linked at positions 1 and 3; (iii) 0.1-0.7 wt % glucose linked at positions 1 and 4; (iv) 7.7-8.6 wt % glucose linked at positions 1, 3 and 6; and (v) about 0.4-1.7 wt % glucose linked at (a) positions 1, 2 and 6, or (b) positions 1, 4 and 6. Aqueous forms of this composition have enhanced viscosity profiles. Further disclosed are methods of using compositions comprising dextran, such as increasing the viscosity of an aqueous composition. Enzymatic reactions for producing dextran are also disclosed.