Biotransformation of Tetrahydrocannabinol

Cannabinoids are terpenophenolic compounds consisting of an aromatic polyketide and derived from the geranyl diphosphate C₁₀ terpenoid unit. They are the active constituents in Cannabis sativa and have been utilized in a number of cannabis-based medicines. Biotransformation of cannabinoids is an important field of xenobiochemistry and toxicology and the study of the metabolism of these compounds can lead to the discovery of new compounds, unknown metabolites with unique structures and new therapeutic entities. Different fungi, bacteria, plants and animal cells have been used for the regio- and stereoselective transformation of cannabinoids. All of the above mentioned organisms have distinct enzymes which catalyze the conversion of a specific cannabinoid at different positions and thus provide a variety of derivatives. All organisms are able to transform the alkyl side chain where as mammalians are unique in the formation of the carboxy derivatives. This review article assesses the current knowledge on the biotransformation of tetrahydrocannabinol and with particular focus on ?⁹-THC.