Linalool () refers to two of a naturally occurring terpene alcohol found in many and spice plants.[ Linalool has multiple commercial applications, the majority of which are based on its pleasant scent (floral, with a touch of spiciness).]
A colorless oil, linalool is classified as an acyclic monoterpenoid.[ In plants, it is a metabolite, a Essential oil component, an antimicrobial agent, and an aroma compound.][ Linalool has uses in manufacturing of soaps, fragrances, as flavors, household products, and .][ of linalool are referred to as linalyl, e.g. linalyl pyrophosphate, an isomer of geranyl pyrophosphate.]
The word linalool is based on linaloe (a type of wood) and the suffix .[: "International Scientific Vocabulary, from Mexican Spanish lináloe"] In food manufacturing, it may be called coriandrol.[
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Occurrence
Both forms are found in nature: ( S)-linalool is found, for example, as a major constituent of the essential oils of coriander ( Coriandrum sativum L.), cymbopogon ( Cymbopogon martini var. martinii), and sweet orange ( Citrus sinensis) flowers. ( R)-linalool is present in lavender ( Lavandula officinalis), bay laurel ( Laurus nobilis), and sweet basil ( Ocimum basilicum), among others.
Each enantiomer evokes distinct neural responses in humans, so each is classified as possessing distinct . ( S)-(+)-Linalool is perceived as sweet, floral, petitgrain-like (odor threshold 7.4 ppb) and the ( R)-form as more woody and lavender-like (odor threshold 0.8 ppb).
Over 200 species of plants produce linalool, notably from the families Lamiaceae (Mentha and other herbs), Lauraceae (laurels, cinnamon, Aniba rosaeodora), and Rutaceae (citrus fruits), but also birch trees and other plants, from tropical to boreal climate zones.
It was first synthesized in the laboratory of Leopold Ružička in 1919.[Albert Eschenmoser: "Leopold Ruzicka - From the Isoprene Rule to the Question of Life's Origin" CHIMIA 44 (1990)]
Production
Linalool is produced commercially from several terpenes and terpenoid precursors, which are often components of terpentine. 2-Pinanol, derived from pinene, gives linalool upon pyrolysis.
Biosynthesis
In Vascular plant linalool is formed by rearrangement of geranyl pyrophosphate (GPP).
Odor and flavor
Linalool has complex odor and flavor properties. Its odor is similar to floral, spicy wood, somewhat resembling French lavender plants, bergamot oil or lily of the valley.[ It has a light, citrus-like flavor, sweet with a spicy tropical accent.][ Linalool is used as a scent in hygiene products and cleaning agents, including , , , and lotions.]
Chemical derivatives
Linalool is hydrogenated to give dihydro- and tetrahydrolinalool, which are fragrances that are more resilient toward oxidants, as might be found in household cleaning products. Linalyl acetate, a popular scent, is produced by esterification of linalool (as well as occurring naturally). Isomerization of linalool gives geraniol and nerol.
Safety
Linalool can be absorbed by inhalation of its aerosol and by oral intake or skin absorption, potentially causing irritation, pain and allergy reactions.
The US Food and Drug Administration (FDA) lists linalool in the Code of Federal Regulations under substances generally recognized as safe, synthetic flavoring substances and adjuvants.
See also
External links
