According to the present invention, a crystal of ammonium N-acetylneuraminate anhydrate, and a process for producing a crystal of ammonium N-acetylneuraminate anhydrate, comprising adding or adding dropwise a solvent selected from the group consisting of alcohols and ketones to an aqueous N-acetylneuraminic acid solution containing an ammonium-containing compound and having a pH of 3.0 to 9.0 to precipitate a crystal of ammonium N-acetylneuraminate anhydrate, and collecting the crystal of ammonium N-acetylneuraminate anhydrate from the aqueous solution, can be provided.

The present inventions provides drug-drug conjugates, drug-porphyrin conjugates, nanoparticles of the conjugates, as well as modified nanoparticles having PEGylated exteriors or encapsulated by red blood cell vesicles. The conjugates, nanoparticles and nanocarriers are useful for treating cancers and other diseases, as well as for imaging diseased tissue or organs.

The present invention concerns an efficient way to isolate L-fucose from a fermentation broth. The L-fucose contained in the fermentation broth is produced by microbial fermentation (bacterial or yeasts). The inventive process comprises a step of removing biomass from the fermentation broth, a step of subjecting the resulting solution to at least one of a cationic ion exchanger treatment and an anionic ion exchanger treatment and a step of removing salts after the ion exchanger treatment. The process can provide L-fucose in powder form, in granulated form as well as in form of L-fucose crystals.

The present invention concerns an efficient way to isolate L-fucose from a fermentation broth. The L-fucose contained in the fermentation broth is produced by microbial fermentation (bacterial or yeasts). The inventive process comprises a step of removing biomass from the fermentation broth, a step of subjecting the resulting solution to at least one of a cationic ion exchanger treatment and an anionic ion exchanger treatment and a step of removing salts after the ion exchanger treatment. The process can provide L-fucose in powder form, in granulated form as well as in form of L-fucose crystals.

The present invention describes an efficient way to isolate a sialic acid from a fermentation broth. The sialic acid contained in the fermentation broth is produced by bacterial fermentation. The inventive process comprises a step of removing biomass from the fermentation broth, a step of subjecting the resulting solution to at least one of a cationic ion exchanger treatment and an anionic ion exchanger treatment and a step of removing salts after the ion exchanger treatment. The process can provide the sialic acid in spray-dried form as well as in form of sialic acid crystals.

The present invention describes an efficient way to isolate a sialic acid from a fermentation broth. The sialic acid contained in the fermentation broth is produced by bacterial fermentation. The inventive process comprises a step of removing biomass from the fermentation broth, a step of subjecting the resulting solution to at least one of a cationic ion exchanger treatment and an anionic ion exchanger treatment and a step of removing salts after the ion exchanger treatment. The process can provide the sialic acid in spray-dried form as well as in form of sialic acid crystals.

An object of the present invention is to provide a crystal of 3′-sialyllactose (hereinafter, referred to as 3SL), which is easily handled, and has high storage stability at normal temperature as well as under high temperature conditions, and provide a process for producing the same. The present invention relates to a 3SL sodium salt n-hydrate (wherein n represents any number of 0 to 9, and when n is 0, it is referred to as 3SL sodium salt anhydrate) and a process for producing the same.

The present inventions provides drug-drug conjugates, drug-porphyrin conjugates, nanoparticles of the conjugates, as well as modified nanoparticles having PEGylated exteriors or encapsulated by red blood cell vesicles. The conjugates, nanoparticles and nanocarriers are useful for treating cancers and other diseases, as well as for imaging diseased tissue or organs.

The cell labeling agent includes a monosaccharide derivatives with a six-membered ring structure that are metabolized to sialic acid in the sialic acid biosynthetic pathway of cells. Among the groups bonded to carbon atoms constituting a six-membered ring in the monosaccharide derivatives, at least one group that does not change, even when metabolized by the sialic acid biosynthetic pathway, includes a ring structure with a carbon-carbon double bond or triple bond.

The present invention provides sialic acid analogs and their compositions useful for the treatment of sialic acid deficiencies.