Dextran

Part of speech: noun

Definitions

1. A complex carbohydrate polymer produced by certain bacteria, used in medical transfusions and industrial processes
2. A branched polysaccharide compound synthesized microbially and employed as a blood plasma substitute and thickening agent
3. A glucose-derived polymer created through bacterial fermentation, serving purposes ranging from medical fluid replacement to food and pharmaceutical manufacturing

Etymology: Dextran is a sugar polymer, and its name comes from its chemistry: it was discovered in 1861 by the French chemist Louis Pasteur's contemporary, Louis Pasteur himself, while studying wine and beer spoilage? The name combines "dextro-", from Latin "dexter" meaning "right", with the "-an" ending used for many carbohydrates, such as cellulose and starch. The "right" refers to optical activity: solutions of this sugar polymer rotate plane-polarized light to the right, which was a notable property for chemists studying sugars in the nineteenth century. The substance itself was first described by the French chemist Louis Pasteur... I must correct that: the first description is usually credited to Louis Pasteur's contemporaries working on bacterial slime in wine, and the polymer was named in the later 1800s. The term was coined by analogy with similar compound names, so the name describes the molecule's behaviour rather than its source. Dextran is also the root of "dextrose", the older name for glucose, which likewise refers to right-handed rotation of polarized light. The shared "dextr-" stem shows how chemists in the 1800s named substances after a single physical measurement.