NOOTKATONE

Description

Nootkatone has a pleasant taste. It may be prepared by oxidation of valencene (a sesquiterpene) with tertiary butyl chromate.

Description

(+)-Nootkatone is sesquiterpene ketone originally isolated from grapefruit juice and peel oil with diverse biological activity. It is lethal against ticks, fleas, and mosquitoes with LC₅₀ values of 0.0029, 0.0061, and 0.0046% w/v, respectively. Pretreatment of wood with (+)-nootkatone reduces tunnel lengths, feeding, and survival rates in C. formosanus termites. (+)-Nootkatone (10-100 μM) dose-dependently activates AMPKα1 and AMPKα2 in C₂C₁₂ mouse myoblast lysate containing a substrate peptide. It dose-dependently inhibits platelet aggregation induced by collagen, thrombin , and arachidonic acid when used at concentrations ranging from 10 to 100 μM with almost complete inhibition at the highest concentration. In vivo, (+)-nootkatone (3-30 mg/kg, p.o.) dose-dependently increases the length of tail bleeding time in mice. (+)-Nootkatone (0.1-0.3%, p.o.) dose-dependently reduces body weight and plasma glucose levels in mice fed a high-fat and high-sucrose diet.

Chemical properties

viscous yellow liquid or crystals with a citrus odour;

Chemical properties

NOOTKATONE has been isolated from grapefruit peel and juice and identified in other citrus oils as well. The commercially available product is a colorless to yellowish liquid with a typical grapefruit odor.
Nootkatone can be prepared by oxidation of valencene, a sesquiterpene hydrocarbon isolated from orange oils. The oxidation can be accomplished either by chemical or by biotechnological methods.
Nootkatone is used for flavoring beverages.

Chemical properties

Nootkatone has a powerful fruity sweet, citrusy, grapefruit peel oil-like aroma.

Occurrence

Reported found in grapefruit oil and juice; traces are also reported found in the oils of bergamot, lemon, lime, orange and tangerine; also reported formed in canned orange juice on storage.

The Uses of NOOTKATONE

Nootkatone is an effective repellent/insecticide against mosquitos, and may repel bed bugs, head lice and other insects. Nootkatone in spray form has been shown as an effective repellent/insecticide against deer ticks and lone star ticks.

Definition

ChEBI: A sesquiterpenoid that is 4,4a,5,6,7,8-hexahydronaphthalen-2(3H)-one which is substituted by methyl groups at positions 4 and 4a, and by an isopropenyl group at position 6 (the 4R,4aS,6R stereoisomer).

Preparation

By oxidation of valencene (a sesquiterpene) with tertiary butyl chromate.

Aroma threshold values

Detection: 170 to 800 ppb

Taste threshold values

Taste characteristics at 20 ppm: grapefruit, citrus, orange and butter.

General Description

(+)-nootkatone, a bicyclic conjugated sesquiterpene ketone with a grapefruit-like flavor, is commonly used in fragrance, food, cosmetics and pharmaceutical industry. It can be synthesized from (+)-valencene via biotransformation. (+)-nootkatone is the active ingredient responsible for the antiplatelet effect of Cyperus rotundus, a well-known oriental traditional medicine. It also shows promising efficacy against Staphylococcus aureus biofilms.