Fucose (Fuc), a monosaccharide present at the core of the termini of glycans, critically regulates various biological phenomena and is associated with various diseases. Specifically, detecting Fuc residues or inhibiting the fucosylation pathway is pivotal in understanding the mechanisms of how fucosylated glycans are related to biological processes and diseases and in developing novel therapeutic agents. Fucose is a 6-deoxyhexose having the “galacto” configuration—that is, it has cis-hydroxyl groups on C-3 and C-4[1].

D-fucose (5-methyl-l-arabinose), also known as alpha-D-fuc or α-D-fucp, belongs to the class of organic compounds known as hexoses. D-fucose, a close structural analogue of l-arabinose, blocks the growth of cells on arabinose. D-Fucose is usually found in plants and some microorganisms in relatively simple glycosides comprising only a few sugar units.

L-fucose is a six-carbon sugar also known as 6-deoxy-l-galactose. Its molecular formula is C6H12O5, and its melting point is 150.0–153.0 °C. It is a white crystalline powder that easily absorbs moisture, and its hydrophilicity is weaker than other monosaccharides. L-fucose is the main form of fucose found in nature and is also the only levorotatory sugar used by mammals, while d-fucose is found only in some glycosides[2]. L-fucose has many biological functions, such as the antitumor effect and relieving intestinal disease, and it exhibits potential as an emulsifier in the food industry. It can be used as a functional food and one of the components of bacteriostatic agents. Moreover, it also has an anti-ageing function.