A new hydrogel made of crosslinked glycosaminoglycans, particularly crosslinked hyaluronic acid, chondroitin or chondroitin sulfate, having reversible linkages using boronic acid or boroxole derivatives leading to new benefits. Glycosaminoglycans that are crosslinked via an alkoxyboronate ester anion formed between a diol portion of a diol-functional moiety grafted to a first glycosaminoglycan and a boronate hemiester grafted to a second glycosaminoglycan.

The present invention relates to a process for preparing a crosslinked gel of at least one polysaccharide or a salt thereof, comprising at least the steps consisting in: a) providing a solution formed from an aqueous medium comprising at least said polysaccharide(s) or a salt thereof in a non-crosslinked form, at least one difunctional or multifunctional epoxide crosslinking agent chosen from butanediol diglycidyl ether, diepoxyoctane, 1,2-bis(2,3-epoxypropyl)-2,3-ethylene, and mixtures thereof, and at least one phosphate salt; b) crosslinking the solution from step a) and, where appropriate; c) recovering said crosslinked gel formed.

A method of preparing a hydrogel product including crosslinked glycosaminoglycan molecules, said method including: i) providing a glycosaminoglycan crosslinked by amide bonds, wherein the crosslinked glycosaminoglycans include residual amine groups; and ii) acylating residual amine groups of the crosslinked glycosaminoglycans provided in i) to form acylated crosslinked glycosaminoglycans.

The present invention relates to a method for in vivo production of glycosaminoglycans (GAG), by metabolic engineering in a genetically modified cell. In a method according to the invention, said cell is genetically modified in order to express the genes coding for the enzymes that are suitable for synthesizing GAG from an exogenous precursor, preferably internalized by the cell. According to one specific feature, the present invention relates to a method for producing chondroitin or heparosan in a genetically modified bacterial cell, from an exogenous beta-galactoside precursor, preferably internalized by the cell. According to another specific feature, the present invention relates to the use of an Escherichia coli cell comprising at least the genes glcA-T, kfoC, kfiD and wbpP for the production of chondroitin. According to yet another specific feature, the present invention relates to the use of an Escherichia coli cell comprising at least the genes glcA-T, kfiA, kfiB, kfiC and kfiD for the production of heparosan. The present invention also relates to the use of the obtained glycosaminoglycans by implementing a method according to the invention in order to prepare a drug, a food composition or a cosmetic product.

The present invention discloses a depolymerized holothurian glycosaminoglycan composition and a preparation method and application thereof. The composition comprises one or more of depolymerized holothurian glycosaminoglycans with weight-average molecular weight between 2000 Da and 12000 Da. The preparation method of the depolymerized holothurian glycosaminoglycan composition comprises the steps of extracting and purifying holothurian glycosaminoglycan, depolymerizing the holothurian glycosaminoglycan and the like. Anti-tumor studies show that the depolymerized holothurian glycosaminoglycan composition can remarkably inhibit tube formation of human umbilical vein endothelial cells in vitro and inhibit metastasis of melanomas and breast cancer in vivo. With its excellent anti-cancer properties, depolymerized holothurian glycosaminoglycan composition can be used as pharmaceuticals, nutraceuticals and other health products.

The present invention encompasses methods and compositions for generating a biomimetic proteoglycan. The invention includes methods of treating a disease, disorder, or condition of soft tissue using a biomimetic proteoglycan.

Testosteronan, a heparosan analog having the structure [-4-D-GlcUA-1,4-D-GlcNAc-1-].sub.n, is produced by testosteronan synthase, a single protein that is a dual-action catalyst that utilizes UDP-GlcUA and UDP-GlcNAc to synthesize a polysaccharide having the structure [-4-D-GlcUA-1,4-D-GlcNAc-1-].sub.n.

An object of the present invention is provide a method for sulfating a glycosaminoglycan in a solution of a non-organic solvent. In the present invention, sulfation reaction of a glycosaminoglycan is performed with a sulfating agent in a strongly basic solution of a non-organic solvent. In the present invention, pH of the strongly basic solution is preferably set to be 11.5 or higher. According to the present invention, for example, a glycosaminoglycan having heparin-like anticoagulant activity can be produced from N-acetylheparosan through one-pot procedure. In one embodiment, a sulfated glycosaminoglycan produced by the method of the present invention has a unique disaccharide composition and is expected to be a novel useful material.

Compositions and methods for inducing an immune response against extra-intestinal pathogenic Escherichia coli (ExPEC) are described. In particular, multivalent vaccines containing E. coli antigen polysaccharide covalently bound to a exotoxin A of Pseudomonas aeruginosa (EPA) carrier protein that can withstand multiple environmental stresses are described.

Oligosaccharides from bovine milk, whey and dairy products, and methods of producing bovine milk oligosaccharides are provided.