Hexoses of Physiologic Importance (Source, Biochemical and Clinical SIgnificance)

D-Mannose

hydrolyzes of plant mannans and gums

D-Glucose

Fruit juices, hydrolysis of starch, cane or beet sugar, maltose and lactose

D-Fructose

Fruit juices, honey, hydrolysis of cane or beet sugar and inulin, enzymatic isomerization of glucose syrups for food manufacture

D-Galactose

Hydrolysis of lactose

D-Glucose

Main metabolic fuel for tissues: "blood sugar"

D-Fructose

readily metabolized either via glucose or directly

D-Galactose

Readily metabolized to glucose; synthesized in the mammary gland for synthesis of lactose in milk. A constituent of glycolipids and glycoproteins

D-Mannose

Constituent of glycoproteins

D-Glucose

Excreted in the urine (glucosuria) in poorly controlled diabetes mellitus as a result of hyperglycemia

D-Fructose

Hereditary fructose intolerance leads to fructose accumulation and hypoglycemia

D-Galactose

Hereditary galactosemia as a result of failure to metabolize galactose leads to cataracts