Thymol
Thymol also known as isopropylmethylphenol, (IPMP) is a monoterpene phenol derivative of cymene, C10H14OH, isomeric with carvacrol, found in oil of thyme, and extracted as a white crystalline substance of a pleasant aromatic odor and strong antiseptic properties. Thymol is only slightly soluble in water, but it is extremely soluble in alcohols and other organic solvents. It is also called "Isopropyl-m-cresol" and "hydroxy cymene".[1]
History
The Ancient Egyptians used thymol and carvacrol in the form of a preparation from the thyme plant (a member of the mint family), because of their ability to conserve mummies. Thymol and carvacrol are now known to kill bacteria and fungi, having made thyme well suited for such purposes.
The crystalline substance thymol was discovered by Caspar Neumann in 1719 and synthesized in pure form in the year 1842 by von M. Lallemand characterized through elementary chemical analysis. Using this, he was able to discover the correct ratio of carbon, hydrogen, and oxygen that make up thymol molecules. Friedrich Ferdinand Runge also studied the chemistry of this substance. Alain Thozet und M. Perrin first published the crystral structure analysis with the exact determination of the structural atoms.
Uses
Thymol has been found to be useful in controlling varroa mites in bee colonies.[2] A minor use is in bookbinding: before rebinding, books with mold damage can be sealed in bags with thymol crystals to kill fungal spores. Thymol has been used in alcohol solutions and in dusting powders for the treatment of tinea (ringworm) infections. It is also used as a preservative in halothane, an anaesthetic, and as an antiseptic in mouthwash.
The Bee Balms (Monarda fistulosa and Monarda didyma) are natural sources of thymol, a primary active ingredient in modern commercial mouthwash formulas. The Blackfeet Native Americans recognized this plant's strong antiseptic action, and used poultices of the plant for skin infections and minor wounds. A tea made from the plant was also used to treat mouth and throat infections caused by dental caries and gingivitis.[3]
Recent medical research on rats concludes that "Thyme extract had relaxing effects on organs possessing β2-receptors (uterus and trachea)."[4]
In a 1994 report released by five top cigarette companies, thymol was listed as one of 599 additives to cigarettes.[5] It is said to be added to improve the flavor of cigarettes, but as mentioned above, it relaxes the trachea.
There is also evidence supporting the belief that thymol when applied two to three times daily, can eliminate certain kinds of fungal infections that affect finger nails and toe nails in humans.[citation needed] Regular application to the affected nail over periods approximating three months, has been shown to eliminate the affliction by effectively preventing further progress;[citation needed] by simply cutting the nail as one normally would, all infected material is eventually eliminated.
Biological activity
Thymol has GABAergic activity,[6] a mechanism of action similar to other depressants such as secobarbital, methaqualone and diazepam. It bears close similarity to the widely used anaesthetic propofol (2,6-diisopropylphenol). Because it is less potent, thymol could potentially be abused like the more common depressants. Propofol is extremely dangerous because of its very steep dose-response curve and high potency. It is commonly abused among anesthesiologists and nurses, many times causing death.[7][8] Because of thymol's lowered potency and safer dose-response curve, it could feasibly be abused as a legal depressant. Because propofol is not scheduled, thymol is neither a controlled substance nor a controlled substance analogue in the US and the UK. Because of its widespread availability in food products, it is unlikely to ever come under control.
See also
References
- ^ Webster's 1913 dictionary)
- ^ Almond farmers seek healthy bees
- ^ Edible and Medicinal Plants of the West, Gregory L. Tilford, ISBN 0-87842-359-1
- ^
Wienkötter, N. (2007). "The Effect of Thyme Extract on β2-Receptors and Mucociliary Clearance". Planta Medica. 73 (7): 629–635. doi:10.1055/s-2007-981535.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ List of 599 Cigarette additives
- ^ Priestley, Caroline M. (2003). "Thymol, a constituent of thyme essential oil, is a positive allosteric modulator of human GABAA receptors and a homo-oligomeric GABA receptor from Drosophila melanogaster". British Journal of Pharmacology (140): 1363–1372. doi:10.1038/sj.bjp.0705542.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ Iwersen-Bergmann S, Rösner P, Kühnau HC, Junge M, Schmoldt A. Death after excessive propofol abuse. International Journal of Legal Medicine. 2001;114(4-5):248-51.
- ^ Kranioti EF, Mavroforou A, Mylonakis P, Michalodimitrakis M. Lethal self administration of propofol (Diprivan). A case report and review of the literature. Forensic Science International. 2007 Mar 22;167(1):56-8. Epub 2006 Jan 23.