Absinth thujone

Plant terpenes may deter herbivores and attract pollinators. They may participate in competition among plants and may act as antibiotics, called phytoalexins, to protect plants from bacteria and fungi.84 In invertebrate animals terpenes serve as hormones, pheromones, and defensive repellants (Figs. 22-3,22-4). The terpene squalene is the precursor to sterols. Some terpenes are toxic. For example, thujone (Fig. 22-3), which is present in the liqueur absinthe, causes serious chronic poison-... 

Specific antagonists for GABAa receptors include the alkaloid convulsants bicuculline (Fig. 30-25)699 and picrotoxin (Fig. 22-4) and the convulsant terpenoid compound thujone (Fig. 22-3), which is present in the wormwood plant Artemesia absinthium. Thujone is present in the liqueur absinthe, which was the national drink of France in the late 19th century but, because of its toxicity, has been illegal in most countries since -1915.719... 

Section 26.8 X fi-Thujone a toxic monoterpene present in absinthe Terpenes and related isoprenoid compounds are biosynthesized from isopentenyl pyrophosphate. 

The thujones are found in true wormwood, Artemisia ahsinthum, a species of mug wort native to Europe and Asia. This plant was once a source for absinthe, a greenish, bitter-tasting alcoholic beverage that has since been banned because of the toxicity of the thujones. The compounds have a peppcrmint-like odor and act as nerve poisons that can be the cause of epileptic fits. Nevertheless, they still find some application in homeopathic medicine... 

Absinthe and a GABA Antagonist What would it feel like if you ingested a drug that blocked the brain s most important inhibitory neurotransmitter Would you become excited Thujone is such a drug it blocks the action of... 

Today, however, it is known that the manner in which absinthe was once prepared would have produced only very low levels of thujone in a typical serving. Therefore, the symptoms noted among chronic users of absinthe more likely resulted... 

Oils may contain toxic compounds. For example, Myristicin is the compound that flavors nutmeg and mace it is also found in black pepper and carrot, parsley, and celery seeds. Used in culinary quantities, myristicin is only a flavoring. In massive doses, it causes hallucination. Thujone, the anise-flavored oil in wormwood, caused an epidemic of brain disease in drinkers addicted to the now-banned liquor absinthe. Sassafras contains a toxic oil similar to thujone, which is why it is no longer used to make root beer. Very high doses of menthol, from peppermint, may cause dangerous irregularities in the heart s rhythm (Weiss, 1997)... 

By the end of this chapter we hope you will be able to recognize some basic classes of natural products and know a bit about their chemistry. We will meet alkaloids such as coniine, the molecule in hemlock that killed Socrates, and terpenes such as thujone, which was probably the toxin in absinthe that killed the nineteenth-century artists in Paris. 

Thujane monoterpenes are based on the bicyclic (G3 C5) monoterpene thujane and include umbellone (thujan-2-one) and the neuroactives a-thujone and 3-thujone (thujan-3-one isomers) that can cause convulsions. Thujones are GABA(A) receptor antagonists and are the active constituents in oil of wormwood from Artemisia absinthium (Asteraceae) used in the alcoholic drink absinthe that was eventually banned because of its deleterious neurotoxic effects. 

SAFETY PROFILE Poison by intravenous, intraperitoneal, and subcutaneous routes. Moderately toxic by ingestion. Serious physiological consequences from abuse of absinthe (mainly in France) led to its aboKtion in 1915. Wormwood is still used in concentrations of less than 10 ppm in flavored wines. Thujone at 30 mg/kg causes convulsions associated with lesions of the cerebral cortex. Little is known of thujone metabolism. Both forms occur in wormwood oil, oak moss. The a form is major constituent of cedar leaf oil or oil of thuja, sage. The p form occurs in tansy, yarrow. When heated to decomposition it emits acrid smoke and irritating fumes. 

Wormwood wines or absinth nowadays have seen something of a revival. However, European regulation limits the thujone content in bitter spirits to 35 mg/kg. 

Absinthe has been used for the fabrication of absinthe liqueur in Central Europe, but is nowadays forbidden owing to the toxicity of thujone to the CNS leading to headache, dizziness, cramps and delirium. Now there exist thujone-free varieties of the plant with even stronger stimulant effects than the normal absinthe. 

Hold, K.M., N.S. Sirisoma, and J.E. Casida (2001). Detoxification of a- and P-thujones (the active ingredients of absinthe) Site specificity and species differences in cytochrome P450 oxidation in vitro and in vivo. Chem. Res. Toxicol. 14, 589-595. 

Thujone is present in yarrow only in trace amounts (Leung and Foster 1996). Some concerns regarding the safety of thujone have been based on the effects of absinthe, an alcoholic beverage that historically contained thujone. 

Recent research, however, indicates that the alcohol content, rather than the thujone content, of absinthe was responsible for the reported adverse effects (Lachenmeier et al. 2006,2008). 

Lachenmeier, D., D. Nathan-Maister, T. Breaux, et al. 2008. Chemical compxisition of vintage preban absinthe with sp>e-cial reference to thujone, fenchone, pinocamphone, methanol, copper, and antimony concentrations. J. Agric. Food Chem. 59(9) 3073-3081. 

A condition known as absinthism was observed in chronic consumers of the alcoholic beverage absinthe, which contains wormwood extract. The condition was described as a form of alcoholism that included delirium, hallucinations, tremors, and seizures (Lee and Balick 2005). While the compound thujone was once thought to be the primary cause of the psychotropic activity and toxicity of absinthe, recent analyses of absinthe indicate that the thujone content of historical and contemporary samples is insignificant and that other ingredients, such as the coloring agents copper sulfate or antimony chloride, may have been responsible for the adverse effects of absinthe (Blaschek et al. 2002 Lachenmeier et al. 2008). 

Deiml, T., R. Haseneder, W. ZiegJgUnsberger, et aL 2004, a-Thujone reduces S-HTg receptor activity by an effect on the agonist-reduced desensitization. Neuropharmacology 46 192-201. Detthng, A., H. Grass, A. Schuff, et al. 2004. Absinthe Attention performance and mood under the influence of thujone. /. Stud. Alcohol 65(5) 573-581. 

It was formerly assumed that thujone (from A. absinthium) was responsible for the alleged psychotropic activity and toxicity of absinthe this notion has recently been... 

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