Gelling dextran ethers

Abstract

Compositions are disclosed herein comprising at least one dextran ether compound that comprises uncharged, anionic, and/or cationic organic groups. The degree of substitution of one or more dextran ether compounds is about 0.0025 to about 3.0. Dextran from which the disclosed ether compounds can be derived can have a weight-average molecular weight of about 50-200 million Daltons and/or a z-average radius of gyration of about 200-280 nm. Also disclosed are methods of producing dextran ether compounds, as well as methods of using these ether compounds in various applications.

1 - 15 . (canceled) 
     
     
         16 . A composition comprising a dextran compound, wherein the dextran compound is a product of an isolated glucosyltransferase enzyme comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:1 or SEQ ID NO:2, and wherein the weight-average molecular weight (Mw) of said dextran compound is 50 million to 200 million Daltons. 
     
     
         17 . The composition of  claim 16 , wherein the z-average radius of gyration of the dextran compound is 200-280 nm. 
     
     
         18 . The composition of  claim 16 , wherein the dextran compound comprises chains linked together within a branching structure, wherein said chains are similar in length and comprise substantially alpha-1,6-glucosidic linkages. 
     
     
         19 . The composition of  claim 18 , wherein the average length of the chains is 10-50 monomeric units. 
     
     
         20 . The composition of  claim 16 , wherein the dextran compound comprises:
 (i) 87-91.5 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) 0.4-1.7 wt % glucose linked at:
 (a) positions 1, 2 and 6, or 
 (b) positions 1, 4 and 6. 
   
     
     
         21 . The composition of  claim 20 , wherein the dextran compound comprises:
 (i) 89.5-90.5 wt % glucose linked at positions 1 and 6;   (ii) 0.4-0.9 wt % glucose linked at positions 1 and 3;   (iii) 0.3-0.5 wt % glucose linked at positions 1 and 4;   (iv) 8.0-8.3 wt % glucose linked at positions 1, 3 and 6; and   (v) 0.7-1.4 wt % glucose linked at:
 (a) positions 1, 2 and 6, or 
 (b) positions 1, 4 and 6. 
   
     
     
         22 . The composition of  claim 16 , wherein the isolated glucosyltransferase enzyme comprises an amino acid sequence that is at least 95% identical to SEQ ID NO:1 or SEQ ID NO:2. 
     
     
         23 . The composition of  claim 16 , wherein the composition is in the form of a household product, personal care product, pharmaceutical product, industrial product, or food product. 
     
     
         24 . The composition of  claim 16 , further comprising said glucosyltransferase enzyme. 
     
     
         25 . The composition of  claim 16 , wherein at least one organic group is in ether linkage to the dextran compound, and wherein the degree of substitution (DoS) of the dextran compound with the organic group is 0.0025 to 3.0. 
     
     
         26 . The composition of  claim 25 , wherein the organic group is a carboxy alkyl, alkyl, or hydroxy alkyl group. 
     
     
         27 . The composition of  claim 26 , wherein the organic group is a carboxymethyl, methyl, ethyl, hydroxypropyl, dihydroxypropyl, or hydroxyethyl group. 
     
     
         28 . The composition of  claim 25 , wherein the organic group is a positively charged organic group. 
     
     
         29 . The composition of  claim 28 , wherein the positively charged organic group comprises a substituted ammonium group. 
     
     
         30 . The composition of  claim 29 , wherein the substituted ammonium group is a trimethylammonium group. 
     
     
         31 . The composition of  claim 25 , wherein one type of organic group is in ether linkage to the dextran compound. 
     
     
         32 . The composition of  claim 25 , wherein two or more different organic groups are in ether linkage to the dextran compound. 
     
     
         33 . The composition of  claim 25 , wherein the composition is in the form of a household product, personal care product, pharmaceutical product, industrial product, or food product. 
     
     
         34 . A method for increasing the viscosity of an aqueous composition, the method comprising:
 contacting a dextran compound as recited in  claim 16  with the aqueous composition, wherein the viscosity of the aqueous composition is increased by the dextran compound compared to the viscosity of the aqueous composition before the contacting step.   
     
     
         35 . A method for increasing the viscosity of an aqueous composition, the method comprising:
 contacting a dextran compound as recited in  claim 25  with the aqueous composition, wherein the viscosity of the aqueous composition is increased by the dextran compound compared to the viscosity of the aqueous composition before the contacting step.   
     
     
         36 . A method of treating a material, said method comprising:
 contacting a material with an aqueous composition comprising a dextran compound as recited in  claim 16 .   
     
     
         37 . A method of treating a material, said method comprising:
 contacting a material with an aqueous composition comprising a dextran compound as recited in  claim 25 .