Harmine

Harmine, also known as telepathine, is a fluorescent harmala alkaloid belonging to the beta-carboline family of compounds. It occurs in a number of different plants, most notably the Middle Eastern plant harmal or Syrian rue (Peganum harmala) and the South American vine Banisteriopsis caapi (also known as "yage" or "ayahuasca"). Harmine reversibly inhibits monoamine oxidase A (MAO-A), an enzyme which breaks down monoamines, making it a RIMA. Harmine selectively binds to MAO-A but does not inhibit the variant MAO-B.

Biosynthesis

Isolated from the plant Peganum Harmala, harmine is an indole alkaloid with the pyrido[3,4-b]indole ring structure that is characteristic of the β-carboline alkaloids. The β-carboline alkaloids include as harmine, harmaline, harman and harmalol. These molecules are heterocyclic amines, biosynthesized through the combination of five- and six-membered ring structures that are derived from an amino acid- either L-tryptophan or tryptamine- which facilitates the formation of an indole ring system.