Galactose

Galactose is a type of sugar that is found in dairy products and some fruits and vegetables. It is a monosaccharide, meaning it is a simple sugar that cannot be broken down into smaller sugars. Galactose is an important source of energy for the body and is used in various metabolic processes. It is also a component of lactose, the sugar found in milk.

Galactose

Chemical structure: HOCH2(CHOH)4CHO

Classification: Monosaccharide

Characteristics:

- A simple sugar with six carbon atoms (hexose)
- A diastereomer of glucose

Sources:

- Lactose (milk sugar)
- Milk and dairy products
- Some fruits and vegetables (e.g., apples, carrots)

Metabolism:

- Converted to glucose-1-phosphate in the liver
- Used as an energy source in the body
- Can accumulate in certain conditions, such as galactosemia

Physiological functions:

- None known

Clinical significance:

- Galactosemia: An inherited metabolic disorder in which the body cannot convert galactose to glucose. Accumulation of galactose can damage the liver, brain, and other organs.
- Lactose intolerance: Inability to digest lactose due to a deficiency of the enzyme lactase. Consuming lactose-containing foods can cause gastrointestinal symptoms.

Industrial applications:

- Used as a sweetener
- Produces galactomannan (used as a thickening agent)
- Used in the synthesis of various chemicals

Historical significance:

- First isolated by Louis-Nicolas Vauquelin in 1815
- Named after the Greek word "gala" meaning "milk"