Linalool (), also called linalol refers to two enantiomers of a naturally occurring terpene alcohol found in many flowers and spice plants. Together with geraniol, nerol, and citronellol, linalool is one of the rose alcohols.

A colorless oil, linalool is classified as an acyclic monoterpenoid.

The word linalool is based on linaloe (a type of wood) and the suffix '. In food manufacturing, it may be called coriandrol.

  • Cinnamomum tamala
  • Cannabis sativa
  • Basil
  • Solidago (goldenrod)
  • Artemisia vulgaris (mugwort)
  • Humulus lupulus (hop)

It was first synthesized in the laboratory of Leopold Ružička in 1919.

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 higher plants linalool is formed by rearrangement of geranyl pyrophosphate (GPP). With the aid of linalool synthase (LIS), water attacks to form the chiral center.

alt=|center|thumb|Linalool [[biosynthesis pathway. Abbreviations used: geranyl diphosphate synthase (GDS), pyrophosphate ester (OPP), isopentenyl pyrophosphate (IPP), dimethylallyl pyrophosphate (DMAPP), geranyl pyrophosphate (GPP). Stereogenic centers are indicated by an asterisk.|654x654px]]

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. The aroma of the laevo enantiomer is described as fresh, floral, woody, natural, and lavender, whilst the dextro enantiomer is described as sweet, floral, petitgrain, and lavender.

Linalool is used as a scent in perfumed hygiene products and cleaning agents, including soaps, detergents, shampoos, 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 allergic reactions. Some 7% of people undergoing patch testing in Europe were found to be allergic to the oxidized form of linalool.

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

  • Lavender oil

References

  • Comprehensive data sheet