L-Menthol

Toxicity

Menthol, DL: ORAL (LD50): Acute: 2900 mg/kg [Rat], 3100 mg/kg [Mouse]. DERMAL (LD50): Acute: 5001 mg/kg Rabbit.

Chemical properties

white to light yellow crystal powde

The Uses of L-Menthol

(1R,2S,5R)-(-)-Menthol (L-Menthol) is the natural form of Menthol. L-Menthol is used as: refreshing agent, food flavor, cool and antipruritic drug, carminative drug. Menthol crystals is used for pers onal care and cosmetics.

The Uses of L-Menthol

L-Menthol is used as a cooling agent that strongly activates TRPM8.(Transient Receptor Potential Cation Channel, Subfamily M, Member 8 is a Protein Coding gene). It is used as analgesic (topical), antipruritic agent. It is used as: refreshing agent, food flavor, cool and antipruritic drug, carminative drug. Menthol crystals is used for pers onal care and cosmetics.

Indications

Used to treat occasional minor irritation, pain, sore mouth, and sore throat as well as cough associated with a cold or inhaled irritants.

Background

Menthol is a covalent organic compound made synthetically or obtained from peppermint or other mint oils. Forming clear or white waxy, crystalline substance, menthol is typically solid at room temperature. (-)-Menthol is the naturally-occurring and main form of menthol, and is assigned the (1R,2S,5R) configuration. Menthol mediates anesthetic properties and anti-irritating properties locally, thus it is widely used to relieve minor throat irritations.

What are the applications of Application

(?)-Menthol is a cooling agent that strongly activates TRPM8

Definition

ChEBI: A p-menthan-3-ol which has (1R,2S,5R)-stereochemistry. It is the most common naturally occurring enantiomer.

Acquired resistance

(1R,2S,5R)-(-)-Menthol (L-Menthol) is the natural form of Menthol. L- and D-menthol are variants of the same molecule, but have a mirror-image structure in relation to each other, like the right and left hand.

General Description

Produced and qualified by HWI pharma services GmbH.
Exact content by quantitative NMR can be found on the certificate.

Flammability and Explosibility

Non flammable

Biological Activity

l-Menthol inhibite the binding of 13 ligands (calcium channels, sodium channels, γ-aminobutyric acid type A (GABAA) receptor, GABA transporter, dopamine transporter, dopamine D4 receptor, adenosine A2a receptor, α2A-adrenergic receptor, histamine H2 receptor, bombesin receptor, angiotensin AT1 receptor, vasopressin V2 receptor, and leukotriene B4 receptor) with relatively high inhibition rates and acts on these ligands over a similar concentration range. It acts as a positive allosteric modulator of the GABAA receptor rather than an agonist. In periaqueductal grey neurons in rat midbrain slices, l-menthol was shown to prolong spontaneous GABAA receptor–mediated inhibitory current, most likely via a mechanism distinct from that of benzodiazepines. It acts on the dopamine D4 receptor and the dopamine transporter. l-menthol inhibits the [3H]-WIN35,428 binding, similar to GBR12909, suggesting that l-menthol inhibits the binding of dopamine to the dopamine transporter and leading to decreased dopamine uptake[1].

Biochem/physiol Actions

Taste at 25 ppm

Pharmacokinetics

Menthol is a covalent organic compound made synthetically or obtained from peppermint or other mint oils. Menthol induces a cooling sensation on the skin upon inhalation, oral ingestion, or topical application by stimulating the cold-sensitive receptors expressed on the skin, without actually causing a drop in the skin temperature.

Safety Profile

Poison by intravenous route. Moderately toxic by ingestion, intraperitoneal, and subcutaneous routes. An eye irritant. Mutation data reported. When heated to decomposition it emits acrid smoke and irritating fumes.

Metabolism

Purification Methods

Crystallise menthol from CHCl3,pet ether or EtOH/water. [Barrow & Atkinson J Chem Soc 638 1939, Beilstein 6 III 133, 6 IV 150.]

References

[1] Umezu T, et al. Identification of novel target molecules of l-menthol. Heliyon, 2021; 7: e07329.