Fructose and mannose metabolism Fructose metabolism: The chemical reactions and pathways involving fructose, the ketohexose arabino-2-hexulose. Fructose exists in a open chain form or as a ring compound. D-fructose is the sweetest of the sugars and is found free in a large number of fruits and honey. Mannose metabolism: The chemical reactions and pathways involving mannose, the aldohexose manno-hexose, the C-2 epimer of glucose. The D-(+)-form is widely distributed in mannans and hemicelluloses and is of major importance in the core oligosaccharide of N-linked oligosaccharides of glycoproteins. GO:0006000 GO:0006013 IEV:0001417 KEGG:map00051 event Carbohydrate Metabolism Alcohol metabolism