Lemons volatile constituents

CH3(CH2)iiCHO, C13H26O, Mr 198.34, i pijkPa 128 °C, df 0.8356, nf 1.4384, occurs in lemon oil and has been identified as a volatile constituent of cucumber. It is a colorless liquid having a fatty-waxy, slightly citrus-like odor. Addition of tridecanal to fragrance compositions imparts fresh nuances in the top note as well as in the dry out. 

Moshonas, M.G., Shaw, P.E., and Veldhuis, M.K. 1972. Analysis of volatile constituents from meyer lemon oil. J. Agric. Food Chem. 20 751-752. 

Monoterpenes, 10-carbon-containing terpenoids, are composed of two isoprene units, and found abundantly in plants, e.g. (+)-limonene from lemon oil, and (—)-linalool from rose oil. Many monoterpenes are the constituents of plant volatile oils or essential oils. These compounds are particularly important as flavouring agents in pharmaceutical, confectionery and perfume products. However, a number of monoterpenes show various types of bioactivity and are used in medicinal preparations. For example, camphor is used in liniments against rheumatic pain, menthol is used in ointments and liniments as a remedy against itching, bitter-orange peel is used as an aromatic bitter tonic and as a remedy for poor appetite and thymol and carvacrol are used in bactericidal preparations. 

Citronellal. 3,7-Dimethyl-b-octenal. C, 11l80. mol wt 154.24. C 77.86%, H 11.76%, O 10.37%. Chief constituent of citrondla oil also found in many other volatile oils, such as lemon, lemon grass, melissa-. Tiemann, Ber. 32, 834 (1899) Spoon. Chem. IFeekbi. S4, 236 (1958). Structure Naves, Bull Soc. Chim. France 1951, 505 Eschinazi, J. Org. Chem. 26, 3072 (1961). 

The crude oil was light lemon-coloured, had an indistinct odour at first, but distinctly a secondary aromatic one. The chief constituents were dextro-rotatory pinene, geraniol, geranyl-acetate, gerany 1-valerian-.ate, a small amount of a sesquiterpene, tc ether with a little volatile a,ldehyde, and most probably a minute quantity of amyl-acetate. No other terpene than pinene was detected and cineol was quite absent. 

The leaves of two other general varieties, either anise scented or lemon scented, have been reported to yield volatile oils with quite different proportions of the above components. The anise scented variety contains methyleugenol (43%) and methylchavicol (32%) as the major components, and the lemon scented variety contains mostly citral (>80%). The main constituents of the essential oil of the leaves of P. racemosa var. terebinthina (Burret) L. R. Landrum are 4-methoxy eugenol (12.6%), a-terpineol (20%), and a-terpineol acetate (27%), while in the essential oil of P. racemosa var. grisea (Kiaersk.) Fosberg, the major constituents are 4-methoxy eugenol (4.5%) and 4-meth-oxy-isoeugenol (75.2%). The leaves also contain abietic acid, a diterpene. Lupeol, a triterpene, was isolated from the leaves of P. racemosa var. ozua (Urban Ekman) L. R. Landrum. ... 

Distilled 1. is produced in far bigger quantities and is different in odor and appearance a pale yellow or almost water-white mobile liquid with a sharp-fresh terpene-like and citrusy odor, reminiscent of - pine oil and - orange oil as well as - lemon oil. The oil is volatile and mainly used in flavor work for carbonated beverages, where it is a main constituent of flavors of the Cola type. 

Tricyclic skeletons are rarely found. Research data indicate that specific cyclases are involved in the synthesis of individual enantiomers [41,63], Monoterpenoids are most often the constituents of volatile oils, which are widely utilized in perfumery and in medicine as carminatives, sedatives, expectorants, and antimicrobial agents. Some most important essential oils are derived from peppermint leaf, lavender, coriander, caraway, lemon peel, turpentine, rosemary, sage, and others. 

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