Glukose

Glukose, also spelled glucose in many languages, is a simple sugar (monosaccharide) with the molecular formula C6H12O6. It is an aldohexose and a reducing sugar. In solution it exists primarily as cyclic hemiacetals and interconverts between the alpha and beta anomers through mutarotation; the D-enantiomer is the form most commonly found in nature.

Glucose occurs widely in nature and is a central metabolite in energy production. It is produced by photosynthesis in plants and is obtained from dietary carbohydrates or synthesized in animals via gluconeogenesis. Glucose is stored as glycogen in liver and muscle, and in plants as starch for short-term energy storage.

In metabolism, glucose is phosphorylated to glucose-6-phosphate by hexokinase or glucokinase, trapping it inside cells. Through glycolysis, it is oxidized to pyruvate with net production of ATP and NADH. In aerobic conditions pyruvate enters the mitochondria for further oxidation; under anaerobic conditions it is reduced to lactate. The pentose phosphate pathway provides NADPH and ribose-5-phosphate for biosynthesis and nucleotide production.

Glucose is transported into cells by GLUT family transporters; its uptake is regulated by hormones such as insulin and glucagon, helping to maintain normal blood glucose levels. Industrially, glucose is produced by hydrolysis of starch and is used in foods, fermentation, and as a starting material for a wide range of biochemicals and polymers.