Sulphur compounds essential oils

Essential oils may comprise volatile compounds of terpenoid or non-terpe-noid origin. All of them are hydrocarbons and their oxygenated derivatives. Some may also contain nitrogen or sulphur derivatives. They may exist in the form of alcohols, acids, esters, epoxides, aldehydes, ketones, amines, sulphides, etc. Monoterpenes, sesquiterpenes and even diterpenes constitute the composition of many essential oils. In addition, phenylpropanoids, fatty acids and their esters, or their decomposition products are also encountered as volatiles [1-16, 21-33, 36-38]. 

Other compounds, containing sulphur or nitrogen, may be present in some oils (like onion, garlic).Investigations on the solubility of pure essential-oil components in carbon dioxide showed that the separation of terpene hydrocarbons and oxygenated derivatives by fractionated extraction is difficult, since their solubility behaviours and vapour pressures are almost the same. Saturating the CO2 with water as modifier can increase the differences in solubility [78],... 

Vernin G., Metzger J., GC-MS (El, PCI, NCI, SIM) SPECMA Bank Analysis of Volatile Sulphur Compounds in Garlic Essential Oils. In Essential Oils and Waxes, Linskens HF, Jackson JF, Eds., Springer, Berlin/Heidelberg/New York, pp. 99-130 (1991)... 

The essential oil has a strong smell and the sulphur-containing constituents give the characteristic smell and taste. Depending on the method of production the amount of active compounds in the oil is highly variable, which has an influence on the pharmacological effects. 

Bicchi, C., C. Frattini, G. Pellegrino, P. Rubiolo, V. Raverdino, and G. Tsoupras, 1992. Determination of sulphurated compounds in Tagetes patula cv. nana essential oil by gas chromatography with mass spectro-metric, Fourier transform infrared and atomic emission spectrometric detection, 609 ... 

Hur. M-H., Park, J., Maddock Jennings, W, Kim, D. O., Lee, M. S. 2007. Reduction of mouth malodour and volatile sulphur compounds in intensive care patients using an essential oil mouthwash. 

Polyolefins from Dictyopiieris.— The genus Dictyopteris is one of the few genera of seaweed possessing odour, and the major constituents of its essential oil have been shown to be the seven Cu hydrocarbons (61)—(67). During 1971, Moore and collaborators reported the presence of several sulphur-containing compounds (68)—(73) in Dictyopteris, which could be the precursors of the hydrocarbons. Further analysis of Hawaiian Dictyopt-... 

Ch. II., The Constituents of Essential Oils and Synthetic Perfume Bodies. — Hydrocarbons—Sesquiterpenes —Alcohols—Terpene Alcohols—Esters— Aldehydes—Ketones— Phenols and Phenolic Compounds—Oxides and Lactones— Nitrogen Compounds — Sulphur Compound—Free Acids. 

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