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Glucose

life science Maturity 9-11 Next article →

Glucose is a simple sugar that serves as a fundamental building block for life. Chemically, it is a monosaccharide, which means it is a single sugar unit. It is an aldohexose because it contains six carbon atoms and an aldehyde group.

D-Glucose Keilstrich
D-Glucose Keilstrich

This molecule is the most abundant monosaccharide in the world. It is essential for energy and structure in almost every living organism. Because it is so vital for health, the World Health Organization includes glucose as an essential medicine.

Soluţie glucoză 5%
Soluţie glucoză 5%

The way glucose is made and used involves complex biological processes. Plants and most algae create glucose through photosynthesis. They use water and carbon dioxide to build these sugar molecules. Once made, plants use glucose to create cellulose. Cellulose is a polysaccharide that forms strong cell walls.

Alpha-D-Glucopyranose
Alpha-D-Glucopyranose

All living organisms also use glucose to produce adenosine triphosphate, or ATP. ATP acts as the primary energy currency for cells. To manage energy, organisms store glucose as larger polymers. Plants store it as amylose and amylopectin. Animals store it as glycogen. When an animal needs energy, it breaks down glycogen through a process called glycogenolysis.

Glucose metabolism
Glucose metabolism

Glucose molecules can take different shapes depending on their environment. In a straight line, the molecule is in an open-chain or acyclic form. However, it often folds into a ring-like or cyclic structure. This is common because of the alcohol and aldehyde groups in the molecule. In water, glucose exists mostly as pyranose rings. These can be in two different forms called alpha or beta.

Alpha-D-Glucofuranose
Alpha-D-Glucofuranose

Scientists also study different versions called stereoisomers. The most common natural form is D-glucose. A different version, L-glucose, is produced synthetically in small amounts. L-glucose is less biologically active than the natural D-form.

Beta-D-Glucofuranose
Beta-D-Glucofuranose

Humans have a long history of studying this important molecule. Andreas Marggraf first isolated glucose from raisins in 1747. Later, in 1792, Johann Tobias Lowitz discovered it in grapes. He was able to show it was different from cane sugar, known as sucrose. In 1838, Jean-Baptiste Dumas coined the term "glucose." The name comes from Ancient Greek words for "sweet wine."

Glucose Fructose Mannose Gleichgewicht
Glucose Fructose Mannose Gleichgewicht

Friedrich August Kekulé once called it dextrose. He chose this name because it turns polarized light to the right. This helped scientists distinguish it from other sugars.

Many researchers have won Nobel Prizes for their work on glucose. Hermann Emil Fischer won the Nobel Prize in 1902. He mapped the structure of sugars and helped validate theories of chemical bonds. Otto Meyerhof won a prize in 1922 for studying glucose metabolism. In 1929, Hans von Euler-Chelpin and Arthur Harden won for studying sugar fermentation. In 1947, Bernardo Houssay and the duo Carl and Gerty Cori won for their work on glucose metabolism and glycogen. Finally, Luis Leloir won in 1970 for discovering how sugar nucleotides are used to build carbohydrates.

In commercial settings, glucose is often called dextrose. It is frequently manufactured from plant starches. In the United States and Japan, it comes from corn starch. In Europe, it is often made from potato or wheat starch. In tropical areas, it is made from tapioca starch.

Ministry of Information First World War Official Collection Q28219
Ministry of Information First World War Official Collection Q28219

You can find glucose in two main forms: monohydrate and anhydrous. Dextrose monohydrate has about 9.5% water by mass. It is often used in food products like beverage mixes. Anhydrous dextrose has no water attached to it. It is more stable and has a longer shelf life.

Glucose 2
Glucose 2

Because it is dry, it is used in medical tests like the oral glucose tolerance test.

Glucose connects many different fields of science. In chemistry, it helps us understand organic structures and chemical kinetics. In biology, it is the center of energy metabolism and cellular function. In medicine, it is a critical tool for treating patients through intravenous solutions. Whether it is found in honey or used in a lab, glucose remains one of the most important substances on Earth.

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🖼️ Images & Media (16)
File:D-Glucose Keilstrich.svg
D-Glucose Keilstrich.svg
File:Alpha-D-Glucofuranose.svg
Alpha-D-Glucofuranose.svg
File:Beta-D-Glucofuranose.svg
Beta-D-Glucofuranose.svg
File:Alpha-D-Glucopyranose.svg
Alpha-D-Glucopyranose.svg
File:Beta-D-Glucopyranose.svg
Beta-D-Glucopyranose.svg
File:Alpha glucose views.svg
Alpha glucose views.svg
File:Alpha-D-glucose and beta-D-glucose acid-catalyzed mechanism.svg
Alpha-D-glucose and beta-D-glucose...
File:Mutarotation D-Glucose V.1.png
Mutarotation D-Glucose V.1.png
File:Glucose Fructose Mannose Gleichgewicht.png
Glucose Fructose Mannose Gleichgewicht.png
File:Metabolism of common monosaccharides, and related reactions.png
Metabolism of common monosaccharides, and...
File:Glucose metabolism.svg
Glucose metabolism.svg
File:Glucose catabolism intermediates de.png
Glucose catabolism intermediates de.png

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