lecithos

Lecithos is a Greek term meaning egg yolk. In scientific usage, the root lecith- appears in words such as lecithin, which refers to a group of phospholipids originally isolated from egg yolk. The name lecithin derives from the Greek lekithē (egg yolk) with the chemical suffix -in, reflecting its historical origin.

In biochemistry, lecithin denotes a mixture of phospholipids that includes phosphatidylcholine as a major component, along with phosphatidylethanolamine and other related lipids. These compounds are amphipathic, with hydrophilic heads and hydrophobic tails, enabling them to form lipid bilayers. Lecithins play a central role in cell membrane structure and function and act as natural emulsifiers in various biological and industrial contexts.

Historically, lecithin was first isolated from egg yolk in the 19th century by French chemist Théodore Gobley, leading to widespread study of its properties. Today, lecithin is derived not only from egg yolk but also from plant sources such as soy, sunflower, and rapeseed. These plant-derived preparations are commonly used as food additives and cosmetic ingredients, valued for their emulsifying and texture-modifying properties. In nutrition and pharmacology, lecithin-containing products are marketed as dietary supplements and excipients.

See also: Phospholipids, Phosphatidylcholine, Emulsification, Egg yolk, Plant-derived lecithin.