Nootkatone is a natural
organic compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. T ...
, a sesquiterpenoid, and a
ketone that is the most important and expensive aromatic of
grapefruit, and which also occurs in other organisms.
Previously, nootkatone was thought to be one of the main chemical components of the smell and flavour of grapefruits. In high purity, it usually is found as colorless
crystal
A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macro ...
s. Crude extractives are
liquid,
viscous
The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water.
Viscosity quantifies the inte ...
, and
yellow
Yellow is the color between green and orange on the spectrum of light. It is evoked by light with a dominant wavelength of roughly 575585 nm. It is a primary color in subtractive color systems, used in painting or color printing. In the ...
. Nootkatone typically is extracted from grapefruit through the chemical or biochemical
oxidation
Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a ...
of
valencene. It is found in
Alaska yellow cedar trees, as well as in
vetiver grass
''Chrysopogon zizanioides'', commonly known as vetiver and khus, is a perennial bunchgrass of the family Poaceae.
Vetiver is most closely related to ''Sorghum'' but shares many morphological characteristics with other fragrant grasses, such as ...
.
Mechanism of action
As is true of other plant terpenoids, nootkatone activates α-adrenergic type 1
octopamine
Octopamine (molecular formula C8H11NO2; also known as OA, and also norsynephrine, ''para''-octopamine and others) is an organic chemical closely related to norepinephrine, and synthesized biologically by a homologous pathway. Octopamine is ofte ...
receptor (PaOA1) in susceptible
arthropods, causing fatal spasms.
Natural origin
Nootkatone was isolated from the wood of the
Alaskan yellow cedar, ''Cupressus nootkatensis''. The species name, nootkatensis, is derived from the language of the
Nuu-Chah-Nulth
The Nuu-chah-nulth (; Nuučaan̓uł: ), also formerly referred to as the Nootka, Nutka, Aht, Nuuchahnulth or Tahkaht, are one of the indigenous peoples of the Pacific Northwest Coast in Canada. The term Nuu-chah-nulth is used to describe fifte ...
people of Canada (formerly referred to as the Nootka people).
Uses
Nootkatone in spray form has been shown as an effective repellent or
insecticide against
deer ticks and
lone star ticks.
It is also an effective repellent or insecticide against mosquitos, and may repel bed bugs, head lice, and other insects.
It is an environmentally friendly insecticide because it is a volatile essential oil that does not persist in the environment.
It was approved by the U.S. EPA for this use on August 10, 2020. Its ability to repel ticks, mosquitoes, and other insects may last for hours, in contrast to other plant-based oil repellants like citronella, peppermint oil, and lemongrass oil.
It is nontoxic to humans, is an approved food additive,
and is commonly used in foods, cosmetics, and pharmaceuticals.
The
CDC
The Centers for Disease Control and Prevention (CDC) is the national public health agency of the United States. It is a United States federal agency, under the Department of Health and Human Services, and is headquartered in Atlanta, Georgi ...
has licensed patents to two companies to produce an insecticide and an insect repellant.
Allylix, of San Diego, California (Now Evolva), is one of these licensees,
which has developed an enzyme fermentation process that will produce nootkatone more cost effectively than former processes.
See also
*
Grapefruit mercaptan
References
{{reflist
External links
Description of nootkatone at Leffingwell.com
Flavors
Enones
Sesquiterpenes
Decalins
Alkene derivatives