Essential oils fenchone

The chemistry of fenchyl alcohol, Cj HjgO, must be regarded as in a somewhat unsettled state, as questions of isomerism arise which are as yet unsolved. It was ori nally prepared by Wallach by reducing the ketone fenchone, a natural constituent of several essential oils, by means of sodium. Later he obtained it in fairly large quantities as a byproduct in the preparation of fenchone-carboxylic acid, by passing a current of C(X through an ethereal solution of fenchone in the presence of sodium. Fenchyl alcohol has, so far, been found in one essential oil only, namely, that of the root wood of Pinus palustris. 

The two enantiomers of fenchone occur in a number of essential oils. Optically pure (15) (-f)-fenchone has been detected in bitter fennel oil Foeniculum vulgare var. vulgare) and in sweet fennel oil F. vulgare var. dulce) from various sources.It has also been reported to exist in... 

Ravid U, Putievsky E, Katzit I, Ikan R, Chital GC analysis of enantiomerically pute fenchone in essential oils. Flavour Fragr/7 169—172, 1992. 

The root essential oil contains (on average) a-pinene (1.0%), p-cymene (0.3%), /f-lenchyl-acetate (1.0%), trans-anethole (1.6%), eugenol (0.2%), myristicin (3%) and dillapiole (87%). On the other hand, the root and bulbous stem base of Florence fennel contains less than 1% of dillapiole but 70% of trans-anethole, giving a very different taste. The herbage contains 1.00—2.55% essential oil, up to 75% of which is trans-anethole. Anethole and fenchone... 

Many techniques are followed to identify and quantify the components of fennel essential oil. Krizman et al. (2006) developed a headspace-gas chromatography method for analysing the major volatile constituents in fennel fruits and leaves — a-pinene, a-phellandrene, limonene, fenchone, estragole and trans-anethole. 

In summary, Foeniculum is stated to have three species, F. vulgare (fennel), F. azoricum Mill. (Florence fennel) and F. dulce (sweet fennel). Fennel is widely cultivated, both in its native habitat and elsewhere, for its edible, strongly flavoured leaves and seeds. The flavour is similar to, but milder than, that of anise and star anise. Anethole and fenchone are the major constituents of the solvent extract of seed phenols, free fatty acids, carbohydrates, proteins, vitamins and minerals have been reported in varying proportions. In the mature fruit, up to 95% of the essential oil is located in the fruit, greater amounts being found in the fully ripe fruit. Approximately 45 constituents have been determined from fennel seed oil, the main constituents being frans-anethole, fenchone, estragol (methyl chavicol), limonene, camphene, a-pinene and other monoterpenes, fenchyl alcohol and... 

Cyclic Terpenes.— The cyclic terpenes and their oxidation derivatives such as pinene, limonene, menthol, terpineol, cineol, carvone, fenchone and camphor are found in a large number of essential oils... 

Wallach, Otto. (1847-1931). A German chemist who received the Nobel Prize for chemistry in 1910 for his work in alicyhc compounds. His mentors were Hofmann and Wahler, and he worked at the University of Bonn under Kekule. He studied pharmacy and did work on terpenes, camphors, and essential oils. This was followed by research in aromatic oils, perfumes, and spices. He studied thuja oil and fenchone. His research on terpenes revealed their significance in sex hormones and vitamins. Ethereal oils and industrial uses were made possible by his work. 

Lavandula pedunculate subsp. lusitanica (Chaytor) Franco.Thc essential oil and polar extracts of Lavandula pedunculate subsp. lusitanica (Chaytor) Franco collected in south Portugal contain camphor (40.6 %) and fenchone (38.0 %), with hydroxycinnamic acids (3-O-caffeoylquinic, 4-O-caffeoylquinic, S-O-caffeoylquinic, and rosmarinic acids) and flavones (luteolin and apigenin) in the polar extracts. Rosmarinic acid is the main compound in most of them. The bioactive compounds from L. pedunculate polar extracts acts as free-radical scavengers, Fe2+ chelators, and inhibitors of malondialdehyde production, and the essential oil is an active acetylcholinesterase inhibitor [258]. 

Immediately after spraying, evaluation in vis. the constituents of essential oils show uniform blue zones on a yellow background, with the exeptioii of thujone, anisaldehyde and fenchone. 

Thuja occidentalis is, as its common name says, endemic to North America Thuja orientalis to China. Both plants, however, are widely spread now worldwide as ornamental plants. There is no difference in the composition of their terpenes. The main component, also responsible for the toxicity is thujon with more than 50 per cent of the essential oil from Thuja. Furthermore fenchone, campher, sabinene, and terpineol-4, tannins and bitter principles are found, too. 

Pyka et al. separated the selected essential oil components (menthol, (-l-)bomeol, geraniol, linalool, carvone, camphor, (lR)-(-)fenchone) by adsorption thin-layer chromatography using benzene as the mobile phase. Investigated terpenes were characterized by selected topological indices based on connectivity Randic (, ... 

Monoterpenes are important constituents of essential oils. These complex mixtures of compounds, as well as individual monoterpenes are used in medicine (F 2) and industry (F 4). Commercially important monoterpenes are, for instance, menthol, camphor, carvone, thymol, fenchone, and oc-pinene. Monoterpenes flavor foodstuffs and beverages (F 1). Citral, for example, is an important constituent of the smell of lemon. Thymol is involved in the flavor of mandarin oranges. Other monoterpenes, e.g., limonene and geraniol, are constituents of flower scents and attract plant pollinators (E 5.5.1). High monoterpene concentrations in plants will repel most potential predators, but my attract some animals (E 5.5.3). Animals use citronellal, citral, and oc- and jS-pinene als feeding deterrents (E 5.1) and geraniol, geranyl esters, myrcene, and terpinolene as pheromones (E 4). Some monoterpenes, e.g., 1,8-cineole and camphor, are also involved in plant-plant interactions (E 5.3). 

MS and proton NMR spectroscopy have mainly been used for structure elucidation of isolated compounds. However, there are some reports on mass spectrometric analyses of essential oils. One example has been presented by Griitzmacher (1982). The depicted mass spectrum (Figure 2.9) of an essential oil exhibits some characteristic molecular ions of terpenoids with masses at miz 136, 148, 152, and 154. By the application of a double focusing mass spectrometer and special techniques analyzing the decay products of metastable ions, the components anethole, fenchone, borneol, and cineole could be identi ed, while the assignment of the mass 136 proved to be problematic. 

Stimulant oils included jasmine, patchouli, ylangylang, basil, and rosemary active components included fenchone, 1,8 cineole, isoborneol, and orange terpenes (Lis-Balchin, 2006). There was considerable similarity in the sedative and stimulant effects of some essential oils studied physi ologically (e.g., their effect on smooth muscle of the guinea pig in vitro) and in various psychologi cal assessments, mostly on humans (Lis-Balchin, 2006). 

Carum carvi L. (Apiaceae) essential oil is able to kill 5. oryzae, and carvone seems to be the active compound against it. (L)-anethole is proven to be effective against R. dominica. Limonene and fenchone, for example, were active against C. pusillus (Lopez et al., 2008). C. copticum C.B. Clarke volatile oil constituents are thymol, a-terpineol, and p-cymene. Especially S. oryzae was weak against the fumigant action of the essential oil, but also mortality on T. castaneum can be observed (Sahafet al, 2007). 

Bicyclic ketone camphor, formed by oxidation of borneol, is a component of cinnamon, sage and rosemary essential oils. In nature, camphor is formed by the oxidation of borneol, and usually occurs as a mixture of two isomers, (+)-camphor (8-51), which is more common, and (-)-camphor (8-51). Camphor is obtained from the camphor laurel tree wood Camphor officinalis, syn. Cinnamomum camphora, Lauraceae) originating in Indochina, where it grows in large numbers. A further sesquiterpenic ketone is (-)-fenchone (8-51), which is found in many essential oils, for example in fennel essential oil. 

The bulk of the oil boiled between 190 and 220. The following ter-penes were identified in the oil o-pinene, y8-pinene, 1-limonene, dipen-tene, and X-terpinene. A considerable amount of a-terpinene was found (this had previously been identified by Teeple), as well as borneol and methyl-chavicol. Fenchyl alcohol was also found as a constituent of the oil, and traces of camphor and cineol. The presence of fenchyl alcohol is of particular interest as it occurs in the inactive variety. It is well known that this body results from the reduction of fenchone, but it has never before been discovered as a natural constituent of an essential oil The table below shows the character of the fenchyl alcohol occurring in this oil and of those prepared by the reduction of active and inactive fenchone. 

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