Friday, November 19, 2021

History and discovery of terpenes

Terpenes are aromatic compounds found in many plants. The common plant sources of terpenes are tea, thyme, cannabis, Spanish sage, and citrus fruits (e.g., lemon, orange, mandarin). The term 'Terpene' is derived from the term 'turpentine'. They are responsible for the odor of pine trees and for the colors of carrots and tomatoes. β-Carotene, found in carrots, and vitamin A are both terpenes.

The essential oils were used in the ancient Egypt for various ceremonies. Camphor was introduced by Arabs around 11th century.

The method of getting plant essential oils via fatty extraction was identified by the early Middle Ages. The process of distillation of oils from rosemary and sage was described by Arnaud de Villanosa (1th century).

Analyses of oils obtained from plants started by French botanist Jacques-Julien Houtou de Labillardière in 1818. Dumas proposed the name ‘Terpene” derived from turpentine. In 1887, Otto Wallach proposed that isoprenoid unit (5C) is present always in terpenes.

When Otto Wallach began his systematic studies of the terpenes, he observed that individual terpene structures contained multiples of a 5-carbon unit that allowed them to be classified according to the number of such units they contained. The canonical C5 unit proved to be isoprene, which Wallach recognized as the core terpenoid structure.

The structure of camphor was discovered by Bredt in the year 1893, that of pinene via Wagner in year 1894 and that of citral by Tiemann in the year 1895.

The structure of beta carotene from carrot was isolated by Wackenrodder and its correct molecular formula was determined by Will Statter.
History and discovery of terpenes