d-Mannose is a C-2 epimer of d-glucose, which is a natural monosaccharide. It can be obtained from both plants and microorganisms. Chemical synthesis and biotransformation of d-mannose from d-fructose or d-glucose by using d-mannose isomerases, d-lyxose isomerases, and cellobiose 2-epimerase were intensively studied. d-Mannose is an important component of polysaccharides and glycoproteins. It has been widely used in the food, pharmaceutical, and poultry industries, acting as the source of dietary supplements, starting material for the synthesis of drugs and blocking colonization in animal feeds. d-Mannose is a glyconutrient with high research value in basic science because of its structure and function. This article presents a review of current studies on sources, characteristics, production, and application of d-mannose.

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