A French committee vote in 1923 finally gave fats and waxes one name
For a century chemists argued over lipoid, lipin and lipide, each author using the terms differently. On 3 July 1923 an international commission of French biological chemists unanimously adopted lipide, proposed by the pharmacologist Gabriel Bertrand. English speakers dropped the final e, because the French pronounce that last syllable anyway.
Bertrand built his word on the Greek lipos, fat, and deliberately stretched it beyond simple glycerides to take in the more complicated lipoids. That breadth still defines the group today. Lipids cover fats, waxes, sterols, phospholipids and the fat-soluble vitamins A, D, E and K, united less by structure than by shunning water, entirely or at one end. They store energy, carry signals and form the membranes wrapping every cell.
Sorting them had a long run-up. Henri Braconnot in 1815 split greasy substances into solid tallows and fluid oils, and Michel Chevreul soon offered a finer scheme that included waxes, resins, balsams and essential oils. In 1827 William Prout placed fat alongside protein and carbohydrate as one of the major nutrients. Théophile-Jules Pelouze made the first artificial triglyceride, tributyrin, in 1844, and his student Marcellin Berthelot followed with tristearin and tripalmitin.
The picture then widened. Theodore Gobley found phospholipids, which he named lecithins, in mammal brain and hen's egg in 1847, and Johann Thudichum later identified further fatty compounds in human brain tissue, including cephalin, cerebroside and sphingomyelin. Rosenbloom and Gies tried to swap lipoid for lipin in 1912, and Walter Bloor proposed simple, compound and derived lipoids in 1920, only for Bertrand's term to win out three years later.
Modern classification by the Lipid MAPS consortium recognises eight categories, traced to two kinds of building block, ketoacyl and isoprene units. Among them, the sterols include cholesterol in animals, ergosterol in fungal membranes and phytosterols in plants, while the related steroid hormones range from the estrogens and androgens to the forms of vitamin D.
Source: Lipid
