Perfumes limonene

The volatility of a perfume material determines its staying power. The more volatile materials are the ones that evaporate more quickly they tend to dominate the top note of a perfume and to be evident, for example, when sniffing at a freshly opened bottle or jar of a perfumed product or when examining the material on a freshly dipped blotter. The least volatile materials are the ones that stay around, even on fabrics after washing with a perfumed detergent they are most noticeable in the base note of a complex perfume. Limonene and benzyl acetate, for example, have high volatility synthetic musks and benzyl salicylate have low volatility. 

Health and Safety. FEMA has examined cinnamaldehyde and estabhshed its GRAS status (No. 2286). The material has been used in some fragrance compositions, but RJEM (34) has noted its potential for sensiti2ation and limited the use in perfumes for skin contact at 1% in the formula. Eugenol and limonene have been used in conjunction with cinnamaldehyde as quenchers to neutrali2e the irritation reaction that some individuals have toward this aldehyde. 

Linalol is a tertiary alcohol of the formula Cj HjgO, which, with its acetic ester (and traces of other esters) forms the basis of the perfume,of bergamot and lavender oils. By dehydration linalol is converted into terpenes of which the principal are limonene and dipentene, and by esterification into its acetic ester. The examination of the essential oil at different periods of the development of the bergamot fruit has led Charabot and Laloue to the following conclusions. As the fruit matures the essential oil undergoes the following modifications —... 

Plants produce a vast array of terpenes, alkenes built in multiples of five carbon atoms. Many terpenes have characteristic fragrances. For example, the fresh odor of a pine forest is due to pinene, a ten-carbon molecule with a ring structure and one double bond. The fragrances of terpenes make them important in the flavor and fragrance industry. Limonene, another ten-carbon molecule with a ring and two double bonds, is the principal component of lemon oil. Geraniol, a chainlike molecule with two double bonds, is one of the molecules that is responsible for the fragrance of roses and is used in many perfumes. Many other terpenes have important medicinal properties. 

The limonenes are used as fragrance materials for perfuming household products and as components of artificial essential oils. 

The major components of elemi oil are limonene (40-72%), a-phellandrene (10-24%), and the sesquiterpene alcohol elemol (1-25%) [488-491]. Both the resinoid and the oil have a fresh, citrus-like, peppery odor and are used predominantly in soap perfumes. (FCT 1976 (14) p. 755 [8023-89-0] (oil), [9000-74-2] (resin). 

Pinaceae needle oils from Pinaceae species contain (—)-bornyl acetate as their main odoriferous component. Other main constituents are monoterpene hydrocarbons such as a- and /3-pinene, limonene, 3-carene, and a- and /3-phellandrene [713-718b]. The oils are used in perfumes for soap, bath products, and air fresheners and in pharmaceutical preparations. 

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. 

More recently the biotransformation of limonene by another Pseudomonad strain, P. gladioli was reported [76,77]. P. gladioli was isolated by an enrichment culture technique from pine bark and sap using a mineral salts broth with limonene as the sole source of carbon. Fermentations were performed during 4-10 days in shake flasks at 25°C using a pH 6.5 mineral salts medium and 1.0% (+)-limonene. Major conversion products were identified as (+)-a-terpineol and (+)-perillic acid. This was the first time that the microbial conversion of limonene to (+)-a-terpineol was reported, see pathway 4. The conversion of limonene to a-terpineol was achieved with an enzyme, a-terpineol dehydratase (a TD), by the same group [78]. The enzyme, purified more than tenfold after cell-disruption of Pseudomonas gladioli, stereospecifically converted (4 )-(+)-limonene to (4/ )-(+)-a-terpineol or (4S)-(+)-limonene to (4S)-(+)-a-terpineol. a-Terpineol is widely distributed in nature and is one of the most commonly used perfume chemicals [27]. 

Limonene [138-86-3] - [ANALYTICALMETHODS - TRENDS] (Vol 2) -aroma chemical [PERFUMES] (Vol 18) -in Bergamot oil [OILS, ESSENTIAL] (Vol 17) -in caraway oil [OILS, ESSENTIAL] (Vol 17) -in asms oil [OILS, ESSENTIAL] (Vol 17) -in citronella oils [OILS, ESSENTIAL] (Vol 17) -in eucalyptus oil [OILS, ESSENTIAL] (Vol 17) -in expectorants [EXPECTORANTS, ANTITUSSIVES AND RELATED AGENTS] (Vol 9) -m jumperberry oil [OILS, ESSENTIAL] (Vol 17) -in lavender [OILS, ESSENTIAL] (Vol 17) -in lavender [OILS, ESSENTIAL] (Vol 17) -in lime oil [OILS, ESSENTIAL] (Vol 17) -in neroli oil [OILS, ESSENTIAL] (Vol 17) -m oilbanum [OILS, ESSENTIAL] (Vol 17) -in orange oil [OILS, ESSENTIAL] (Vol 17) -in sweet basil oil [OILS, ESSENTIAL] (Vol 17)... 

Although these reactions result in an increased respirable aerosol mass, little is known about human health effects associated with these particular condensed reaction products. Tamas et al. (2006) observed a correlation between the number concentration of SOAs, from the limonene-ozone reaction in an office, and sensory load reported by 20 human subjects. Additionally, a screening study indicates that perfume wearers will be subjected to a personal reactive cloud of reaction products, such as fine aerosols (Corsi et al., 2007). 

Several trial compounds may have to be made before a reasonably close analytical match is obtained. One of the problems that arises at this stage is sorting out the contribution that various components can make to the total quantity of a single ingredient found in the analysis. If citronellol is present, it may be because it occurs as a specified component in the formula, because it comes from a number of different essential oils, or because it is included in one or more bases. Many of the terpenes, such as J-limonene, are present in numerous essential oils, any number of which may be present. Trying to get back to the original formula requires considerable deductive powers and ingenuity on the part of the perfumer. 

It may seem strange to classify a type of bond as a functional group, but you will see later that C=C double bonds impart reactivity to an organic molecule just as functional groups consisting of, say, oxygen or nitrogen atoms do. Some of the compounds produced by plants and used by perfumers are alkenes (see Chapter 1). For example, pinene has a smell evocative of pine forests, while limonene smells of citrus fruits. 

For a review of the chemistry of limonene, see Verghese, J Perfum Essent Oil Rec 1968,... 

D-Limonene may be inhaled when products such as citrus-scented air fresheners, perfumes and candles, cleaners and paints, are used indoors, especially without adequate ventilation. Terpenes are used in products for their solvent properties and, in some cases, for their odor. Limonene is a commonly identified indoor pollutant with time-averaged indoor concentrations in the range of 5-10 ppb, and much higher concentrations (>80ppb) can occur during the use of limonene-containing products. 

D-Limonene can be absorbed through the skin after application of citrus oils, perfumes, soaps, and other fragranced personal care products, and through skin contact with citrus-based cleaning products. 

Traditionally, essential oils were used as beverage flavorings (soft drinks), in the perfume industry and for other chemical uses. In this sense, other applications such as solvents and pesticides have been documented (Braddock, 1999). Furthermore, useful chemicals have been obtained from chemical reactions of limonene (Thomas and Bessiere, 1989). 

The epoxidation of terpenic substrates is of interest in the flavor and fragrance industry [55,56]. Terpenes are derivatives of isoprene, which has formula CsHg (2-methyl-frans-butadiene). There are tens of examples of terpenes, including limonene, a-pinene, geraniol, citronellol, myrcene, ocimene, camphene, a-terpin-eol, menthol, and isopugelol. Limonene is an abundant monoterpene extracted from citrus oil, which can be epoxidized to obtain fragrances, perfumes, and... 

Perhaps a more direct way to assess volatility is to look at the saturated vapour pressure of an ingredient. Saturated vapour pressure refers to the equilibrium pressure exerted by a substance in a closed system at a specified temperature (the volume of the system must, of course, be greater than that of the substance). Table 11.1 again gives representative values. Consider, for example, the volatile material 1,8-cineole (3), which is utilized in many fresh perfumes and is also commonly found in toothpaste flavours. This material has a vapour pressure of ca. 2mmHg at 25 °C (similar to that of limonene), which in the context of the perfumery world is very high. Most musks have vapour pressures that are three to five orders of magnitude smaller than that of cineole. Vapour pressure is directly related to the mass present in the gas phase, so the fact that musks are perceivable at all to the... 

---