α-Pinene is an organic compound of the terpene class, one of two isomers of pinene. It is an alkene and it contains a reactive four-membered ring. It is found in the oils of many species of many coniferous trees, notably the pine. It is also found in the essential oil of rosemary (Rosmarinus officinalis) and Satureja myrtifolia (also known as Zoufa in some regions.) Both enantiomers are known in nature; (1S,5S)- or (−)-α-pinene is more common in European pines, whereas the (1R,5R)- or (+)-α-isomer is more common in North America. The racemic mixture is present in some oils such as eucalyptus oil and orange peel oil.
Properties and usage
At low exposure levels, α-Pinene is a bronchodilator in humans, and is highly bioavailable with 60% human pulmonary uptake with rapid metabolism or redistribution. α-Pinene is an anti-inflammatory via PGE1, and seems to be an antimicrobial. It exhibits activity as an acetylcholinesterase inhibitor, aiding memory. Like borneol, verbenol and pinocarveol (−)-α-pinene is a positive modulator of GABAA receptors. It acts at the benzodiazepinebinding site.
beta-Pinene (β-pinene) is a monoterpene, an organic compound found in plants. It is one of the two isomers of pinene, the other being α-pinene. It is colorless liquid soluble in alcohol, but not water. It has a woody-green pine-like smell.
Plants that contain β-pinene
Many plants from many botanical families contain the compound, including:
- Cuminum cyminum
- Humulus lupulus
- Pinus pinaster
- Clausena anisata
- Cannabis sativa
- Cannabis indica