noun, plural: glucosamines
A hexosamine, where glucose contains an amine (-NH2) instead of hydroxyl (–OH) on the second group, occurs naturally such as in the shells of crustaceans, in the animal bones, and fungi, and marketed as a dietary supplement (usually in combination with chondroitin) to reduce the symptoms of arthritis
An amino sugar is a sugar molecule wherein the hydroxyl group is replaced by an amine group. Hexosamines are amino sugars wherein the sugar derivative is a hexose. Examples of hexosamines are glucosamine (based upon glucose), galactosamine (based upon galactose), fructosamine (based upon fructose), and mannosamine (based upon mannose).
Glucosamine is an amino sugar and a derivative of glucose. It has a chemical formula of C6H13NO5.
In biological systems, one of the functions of glucosamine is to serve as a precursor in the biosynthesis of glycosylated proteins and lipids. It is the biochemical precursor of several amino sugars, including N-acetylglucosamine (C8H15NO6). N-acetylglucosamine is one of the most abundant carbodhydrates. It is an amino sugar that serves as an important component of diverse biological structures (such as bacterial cell wall and peptidoglycan, chitin of insects and crustaceans, radulas of mollusks, beaks of cephalopods, and fungal cell walls).
Glucosamine occurs in the shells of crustaceans, in the animal bones, and fungi. In humans, it is produced from fructose-6-phosphate and glutamine through the catalytic action of glutamine-fructose-6-phosphate transaminase (particularly, in hexosamine biosynthesis pathway).
Glucosamine is produced synthetically, such as by hydrolyzing the exoskeleton of crustaceans or by fermenting grains, such as corn or wheat. It is marketed as a dietary supplement in combination with chondroitin to reduce the symptoms of arthritis. It is marketed in the forms of N-acetylglucosamine, glucosamine sulfate, or glucosamine hydrochloride.