Arecoline

Arecoline is an alkaloid ester found in the seeds of the betel nut palm, which is also called areca palm from its scientific name, Areca catechu. The term “betel nut” is a bit confusing because South and Southeast Asians often chew it along with betel leaf from the vine of the same name (Piper betle). The two plants are not biologically related.

Arecoline has been known since 1891, when German pharmacist E. Jahns isolated it from A. catechu seeds. The first synthesis was reported by Fritz Chemnitius¹ at Jena University (Germany) in 1926. It is a moderately strong base, with a pK_b value of 6.8. It is miscible with water and most organic solvents. The carboxylic acid corresponding to the arecoline ester is called arecaidine; it also exists in betel nuts.

People consume betel nuts because they provide a “high” similar to that caused by nicotine. Arecoline, however, acts on different receptors than does nicotine: muscarinic (rather than nicotinic) acetylcholine receptors, especially M₄, which may be the cause of its effects on the parasympathetic nervous system. Similarly to nicotine, arecoline is addictive. Chewing betel nuts is also dangerous because they contain ingredients that can cause cancers of the mouth and the esophagus.

1. Chemnitius is also known for his 1932 article about chemistry at Jena University from 1629 to 1921.