Coca
Coca is known throughout the world for its psychoactive alkaloid, cocaine. The alkaloid content of coca leaves is relatively low, between 0.25% and 0.77%. The native people use it as a stimulant. Coca-Cola used coca leaf extract in its products from 1885 until about 1903. Extraction of cocaine from coca requires several solvents and a chemical process known as an acid-base extraction, which can fairly easily extract the alkaloids from the plant.
Coca-4