Thymol

Last updated

Contents

Thymol
Thymol2.svg
Thymol3D.png
Names
Preferred IUPAC name
5-Methyl-2-(propan-2-yl)phenol [1]
Systematic IUPAC name
5-Methyl-2-(propan-2-yl)benzenol
Other names
2-Isopropyl-5-methylphenol, isopropyl-m-cresol, 1-methyl-3-hydroxy-4-isopropylbenzene, 3-methyl-6-isopropylphenol, 5-methyl-2-(1-methylethyl)phenol, 5-methyl-2-isopropyl-1-phenol, 5-methyl-2-isopropylphenol, 6-isopropyl-3-methylphenol, 6-isopropyl-m-cresol, Apiguard, NSC 11215, NSC 47821, NSC 49142, thyme camphor, m-thymol, and p-cymen-3-ol
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.001.768 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 201-944-8
KEGG
PubChem CID
UNII
  • InChI=1S/C10H14O/c1-7(2)9-5-4-8(3)6-10(9)11/h4-7,11H,1-3H3 Yes check.svgY
    Key: MGSRCZKZVOBKFT-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C10H14O/c1-7(2)9-5-4-8(3)6-10(9)11/h4-7,11H,1-3H3
    Key: MGSRCZKZVOBKFT-UHFFFAOYAS
  • CC(C)c1ccc(C)cc1O
Properties
C10H14O
Molar mass 150.221 g·mol−1
Density 0.96 g/cm3
Melting point 49 to 51 °C (120 to 124 °F; 322 to 324 K)
Boiling point 232 °C (450 °F; 505 K)
0.9 g/L (20 °C) [2]
1.5208 [3]
Pharmacology
QP53AX22 ( WHO )
Hazards
GHS labelling:
GHS-pictogram-acid.svg GHS-pictogram-exclam.svg GHS-pictogram-pollu.svg
Warning
H302, H314, H411
P260, P264, P270, P273, P280, P301+P312, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P321, P330, P363, P391, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes check.svgY  verify  (what is  Yes check.svgYX mark.svgN ?)

Thymol (also known as 2-isopropyl-5-methylphenol, IPMP), C10H14O, is a natural monoterpenoid phenol derivative of p-Cymene, isomeric with carvacrol, found in oil of thyme, and extracted from Thymus vulgaris (common thyme), ajwain, [4] and various other plants as a white crystalline substance of a pleasant aromatic odor and strong antiseptic properties. Thymol also provides the distinctive, strong flavor of the culinary herb thyme, also produced from T. vulgaris. Thymol is only slightly soluble in water at neutral pH, but it is extremely soluble in alcohols and other organic solvents. It is also soluble in strongly alkaline aqueous solutions due to deprotonation of the phenol. Its dissociation constant (pKa) is 10.59±0.10. [5] Thymol absorbs maximum UV radiation at 274 nm. [6]

Chemical synthesis

Thymol is produced by the alkylation of m-cresol and propene: [7] [8]

CH3C6H4OH + CH2CHCH3 → ((CH3)2CH)CH3C6H3OH

History

Ancient Egyptians used thyme for embalming. [9] The ancient Greeks used it in their baths and burned it as incense in their temples, believing it was a source of courage. The spread of thyme throughout Europe was thought to be due to the Romans, as they used it to purify their rooms and to "give an aromatic flavour to cheese and liqueurs". [10] In the European Middle Ages, the herb was placed beneath pillows to aid sleep and ward off nightmares. [11] In this period, women also often gave knights and warriors gifts that included thyme leaves, because it was believed to bring courage to the bearer. Thyme was also used as incense and placed on coffins during funerals, because it was supposed to ensure passage into the next life. [12]

The bee balms Monarda fistulosa and Monarda didyma , North American wildflowers, are natural sources of thymol. The Blackfoot Native Americans recognized these plants' strong antiseptic action and used poultices of the plants for skin infections and minor wounds. A tisane made from them was also used to treat mouth and throat infections caused by dental caries and gingivitis. [13]

Thymol was first isolated by German chemist Caspar Neumann in 1719. [14] In 1853, French chemist Alexandre Lallemand named thymol and determined its empirical formula. [15] Thymol was first synthesized by Swedish chemist Oskar Widman in 1882. [16]

Extraction

The conventional method of extracting is hydro-distillation (HD), but can also be extracted with solvent-free microwave extraction (SFME). In 30 minutes, SFME yields similar amounts of thymol with more oxygenated compounds than 4.5 hours of hydro-distillation at atmospheric pressures without the need for solvent. [17]

Uses

Thymol Thymolum by Danny S. - 001.JPG
Thymol

Thymol during the 1910s was the treatment of choice for hookworm infection in the United States. [18] [19] People of the Middle East continue to use za'atar, a delicacy made with large amounts of thyme, to reduce and eliminate internal parasites. [20] It is also used as a preservative in halothane, an anaesthetic, and as an antiseptic in mouthwash. When used to reduce plaque and gingivitis, thymol has been found to be more effective when used in combination with chlorhexidine than when used purely by itself. [21] Thymol is also the active antiseptic ingredient in some toothpastes, such as Johnson & Johnson's Euthymol. Thymol has been used to successfully control varroa mites and prevent fermentation and the growth of mold in bee colonies. [22] Thymol is also used as a rapidly degrading, non-persisting pesticide. [23] Thymol can also be used as a medical disinfectant and general purpose disinfectant. [24] Thymol is also used in the production of menthol through the hydrogenation of the aromatic ring. [25]

List of plants that contain thymol

Toxicology and environmental impacts

In 2009, the U.S. Environmental Protection Agency (EPA) reviewed the research literature on the toxicology and environmental impact of thymol and concluded that "thymol has minimal potential toxicity and poses minimal risk". [40]

Environmental breakdown and use as a pesticide

Studies have shown that hydrocarbon monoterpenes and thymol in particular degrade rapidly (DT50 16 days in water, 5 days in soil [23] ) in the environment and are, thus, low risks because of rapid dissipation and low bound residues, [23] supporting the use of thymol as a pesticide agent that offers a safe alternative to other more persistent chemical pesticides that can be dispersed in runoff and produce subsequent contamination. Though, there has been recent research into sustained released systems for botanically derived pesticides, such as using natural polysaccharides which would be biodegradable and biocompatible. [41]

Compendial status

See also

Notes and references

  1. "Front Matter". Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. 2014. p. 691. doi:10.1039/9781849733069-FP001. ISBN   978-0-85404-182-4.
  2. "Thymol". PubChem. Retrieved 1 April 2016.
  3. Mndzhoyan, A. L. (1940). "Thymol from Thymus kotschyanus". Sbornik Trudov Armyanskogo Filial. Akad. Nauk. 1940: 25–28.
  4. O'Connell, John (27 August 2019). The book of spice : from anise to zedoary. New York: Pegasus. ISBN   978-1681774459. OCLC   959875923.
  5. CAS Registry: Data obtained from SciFinder[ full citation needed ]
  6. Norwitz, G.; Nataro, N.; Keliher, P. N. (1986). "Study of the Steam Distillation of Phenolic Compounds Using Ultraviolent Spectrometry". Anal. Chem. 58 (639–640): 641. doi:10.1021/ac00294a034.
  7. Stroh, R.; Sydel, R.; Hahn, W. (1963). Foerst, Wilhelm (ed.). Newer Methods of Preparative Organic Chemistry, Volume 2 (1st ed.). New York: Academic Press. p. 344. ISBN   9780323150422.
  8. Fiege, Helmut; Voges, Heinz-Werner; Hamamoto, Toshikazu; Umemura, Sumio; Iwata, Tadao; Miki, Hisaya; Fujita, Yasuhiro; Buysch, Hans-Josef; Garbe (2000). "Phenol Derivatives". Ullmann's Encyclopedia of Industrial Chemistry . Weinheim: Wiley-VCH. doi:10.1002/14356007.a19_313. ISBN   978-3527306732.
  9. "A Brief History of Thyme - Hungry History". HISTORY.com. Archived from the original on 13 June 2016. Retrieved 9 June 2016.
  10. Grieve, Mrs. Maud. "Thyme. A Modern Herbal". botanical.com (Hypertext version of the 1931 ed.). Archived from the original on 23 February 2011. Retrieved 9 February 2008.
  11. Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Macmillan.
  12. "Thyme (thymus)". englishplants.co.uk. The English Cottage Garden Nursery. Archived from the original on 27 September 2006.
  13. Tilford, Gregory L. (1997). Edible and Medicinal Plants of the West. Missoula, MT: Mountain Press Publishing. ISBN   978-0-87842-359-0.
  14. Neuman, Carolo (1724). "De Camphora". Philosophical Transactions of the Royal Society of London. 33 (389): 321–332. doi: 10.1098/rstl.1724.0061 . On page 324, Neumann mentions that in 1719 he distilled some essential oils from various herbs. On page 326, he mentions that during these experiments, he obtained a crystalline substance from thyme oil, which he called "Camphora Thymi" (camphor of thyme). (Neumann gave the name "camphor" not only to the specific substance that today is called camphor but to any crystalline substance that precipitated from a volatile, fragrant oil from some plant.)
  15. Lallemand, A. (1853). "Sur la composition de l'huile essentielle de thym" [On the composition of the essential oil of thyme]. Comptes Rendus (in French). 37: 498–500.
  16. Widmann, Oskar (1882). "Ueber eine Synthese von Thymol aus Cuminol" [On a synthesis of thymol from cuminol]. Berichte der Deutschen Chemischen Gesellschaft zu Berlin (in German). 15: 166–172. doi:10.1002/cber.18820150139.
  17. Lucchesi, Marie E; Chemat, Farid; Smadja, Jacqueline (23 July 2004). "Solvent-free microwave extraction of essential oil from aromatic herbs: comparison with conventional hydro-distillation". Journal of Chromatography A. 1043 (2): 323–327. doi:10.1016/j.chroma.2004.05.083. ISSN   0021-9673. PMID   15330107.
  18. Ferrell, John Atkinson (1914). The Rural School and Hookworm Disease. US Bureau of Education Bulletin. Vol. 20, Whole No. 593. Washington, DC: U.S. Government Printing Office.
  19. Milton, Joseph Rosenau (1913). Preventive Medicine and Hygiene. D. Appleton. p. 119.
  20. Inskeep, Steve; Godoy, Maria (11 June 2013). "Za'atar: A Spice Mix With Biblical Roots And Brain Food Reputation". NPR. Retrieved 24 February 2022.
  21. Filoche, S. K.; Soma, K.; Sissons, C. H. (2005). "Antimicrobial effects of essential oils in combination with chlorhexidine digluconate". Oral Microbiol. Immunol. 20 (4): 221–225. doi:10.1111/j.1399-302X.2005.00216.x. PMID   15943766.
  22. Ward, Mark (8 March 2006). "Almond farmers seek healthy bees". BBC News. BBC.
  23. 1 2 3 Hu, D.; Coats, J. (2008). "Evaluation of the environmental fate of thymol and phenethyl propionate in the laboratory". Pest Manag. Sci. 64 (7): 775–779. doi:10.1002/ps.1555. PMID   18381775.
  24. "Thymol" (PDF). US Environmental Protection Agency. September 1993.
  25. "Menthol | Definition, Structure, & Uses | Britannica". www.britannica.com. 6 October 2023. Retrieved 30 October 2023.
  26. Novy, P.; Davidova, H.; Serrano Rojero, C. S.; Rondevaldova, J.; Pulkrabek, J.; Kokoska, L. (2015). "Composition and Antimicrobial Activity of Euphrasia rostkoviana Hayne Essential Oil". Evid Based Complement Alternat Med. 2015: 1–5. doi: 10.1155/2015/734101 . PMC   4427012 . PMID   26000025.
  27. Baser, K. H.C.; Tümen, G. (1994). "Composition of the Essential Oil of Lagoecia cuminoides L. from Turkey". Journal of Essential Oil Research. 6 (5): 545–546. doi:10.1080/10412905.1994.9698448.
  28. Donata Ricci; Francesco Epifano; Daniele Fraternale (February 2017). Olga Tzakou (ed.). "The Essential Oil of Monarda didyma L. (Lamiaceae) Exerts Phytotoxic Activity In Vitro against Various Weed Seeds". Molecules (Basel, Switzerland). 22 (2). Molecules: 222. doi: 10.3390/molecules22020222 . PMC   6155892 . PMID   28157176.
  29. Zamureenko, V. A.; Klyuev, N. A.; Bocharov, B. V.; Kabanov, V. S.; Zakharov, A. M. (1989). "An investigation of the component composition of the essential oil of Monarda fistulosa". Chemistry of Natural Compounds. 25 (5): 549–551. doi:10.1007/BF00598073. ISSN   1573-8388. S2CID   24267822.
  30. Escobar, Angélica; Pérez, Miriam; Romanelli, Gustavo; Blustein, Guillermo (1 December 2020). "Thymol bioactivity: A review focusing on practical applications". Arabian Journal of Chemistry. 13 (12): 9243–9269. doi: 10.1016/j.arabjc.2020.11.009 . hdl: 11336/139451 . ISSN   1878-5352.
  31. 1 2 Bouchra, Chebli; Achouri, Mohamed; Idrissi Hassani, L. M.; Hmamouchi, Mohamed (2003). "Chemical composition and antifungal activity of essential oils of seven Moroccan Labiatae against Botrytis cinerea Pers: Fr". Journal of Ethnopharmacology. 89 (1): 165–169. doi:10.1016/S0378-8741(03)00275-7. PMID   14522450.
  32. Liolios, C. C.; Gortzi, O.; Lalas, S.; Tsaknis, J.; Chinou, I. (2009). "Liposomal incorporation of carvacrol and thymol isolated from the essential oil of Origanum dictamnus L. and in vitro antimicrobial activity". Food Chemistry. 112 (1): 77–83. doi:10.1016/j.foodchem.2008.05.060.
  33. Ozkan, Gulcan; Baydar, H.; Erbas, S. (2009). "The influence of harvest time on essential oil composition, phenolic constituents and antioxidant properties of Turkish oregano (Origanum onites L.)". Journal of the Science of Food and Agriculture. 90 (2): 205–209. doi:10.1002/jsfa.3788. PMID   20355032.
  34. Lagouri, Vasiliki; Blekas, George; Tsimidou, Maria; Kokkini, Stella; Boskou, Dimitrios (1993). "Composition and antioxidant activity of essential oils from Oregano plants grown wild in Greece". Zeitschrift für Lebensmittel-Untersuchung und -Forschung A. 197 (1): 1431–4630. doi:10.1007/BF01202694. S2CID   81307357.
  35. Kanias, G. D.; Souleles, C.; Loukis, A.; Philotheou-Panou, E. (1998). "Trace elements and essential oil composition in chemotypes of the aromatic plant Origanum vulgare". Journal of Radioanalytical and Nuclear Chemistry. 227 (1–2): 23–31. doi:10.1007/BF02386426. S2CID   94582250.
  36. Figiel, Adam; Szumny, Antoni; Gutiérrez Ortíz, Antonio; Carbonell Barrachina, Ángel A. (2010). "Composition of oregano essential oil (Origanum vulgare) as affected by drying method". Journal of Food Engineering. 98 (2): 240–247. doi:10.1016/j.jfoodeng.2010.01.002.
  37. 1 2 Goodner, K.L.; Mahattanatawee, K.; Plotto, A.; Sotomayor, J.; Jordán, M. (2006). "Aromatic profiles of Thymus hyemalis and Spanish T. vulgaris essential oils by GC–MS/GC–O". Industrial Crops and Products. 24 (3): 264–268. doi:10.1016/j.indcrop.2006.06.006.
  38. Lee, Seung-Joo; Umano, Katumi; Shibamoto, Takayuki; Lee, Kwang-Geun (2005). "Identification of volatile components in basil (Ocimum basilicum L.) and thyme leaves (Thymus vulgaris L.) and their antioxidant properties". Food Chemistry. 91 (1): 131–137. doi:10.1016/j.foodchem.2004.05.056.
  39. Moldão Martins, M.; Palavra, A.; Beirão da Costa, M. L.; Bernardo Gil, M. G. (2000). "Supercritical CO2 extraction of Thymus zygis L. subsp. sylvestris aroma". The Journal of Supercritical Fluids. 18 (1): 25–34. doi:10.1016/S0896-8446(00)00047-4.
  40. 74 FR 12613
  41. Campos, Estefânia V. R.; Proença, Patrícia L. F.; Oliveira, Jhones L.; Bakshi, Mansi; Abhilash, P. C.; Fraceto, Leonardo F. (1 October 2019). "Use of botanical insecticides for sustainable agriculture: Future perspectives". Ecological Indicators. 105: 483–495. doi:10.1016/j.ecolind.2018.04.038. hdl: 11449/179822 . ISSN   1470-160X. S2CID   89798604.
  42. The British Pharmacopoeia Secretariat (2009). "Index, BP 2009" (PDF). Archived from the original (PDF) on 11 April 2009. Retrieved 5 July 2009.
  43. "Japanese Pharmacopoeia" (PDF). Archived from the original (PDF) on 22 July 2011. Retrieved 21 April 2010.

Commons-logo.svg Media related to Thymol at Wikimedia Commons

Related Research Articles

<span class="mw-page-title-main">Oregano</span> Species of flowering plant

Oregano is a species of flowering plant in the mint family Lamiaceae. It was native to the Mediterranean region, but widely naturalised elsewhere in the temperate Northern Hemisphere.

<span class="mw-page-title-main">Thyme</span> Herb

Thyme is the herb of some members of the genus Thymus of aromatic perennial evergreen herbs in the mint family Lamiaceae. Thymes are relatives of the oregano genus Origanum, with both plants being mostly indigenous to the Mediterranean region. Thymes have culinary, medicinal, and ornamental uses, and the species most commonly cultivated and used for culinary purposes is Thymus vulgaris.

<span class="mw-page-title-main">Essential oil</span> Hydrophobic liquid containing volatile aroma compounds from plants

An essential oil is a concentrated hydrophobic liquid containing volatile chemical compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the oil of the plant from which they were extracted, such as oil of clove. An essential oil is essential in the sense that it contains the essence of the plant's fragrance—the characteristic fragrance of the plant from which it is derived. The term "essential" used here does not mean indispensable or usable by the human body, as with the terms essential amino acid or essential fatty acid, which are so called because they are nutritionally required by a living organism.

<span class="mw-page-title-main">Phytochemistry</span> Study of phytochemicals, which are chemicals derived from plants

Phytochemistry is the study of phytochemicals, which are chemicals derived from plants. Phytochemists strive to describe the structures of the large number of secondary metabolites found in plants, the functions of these compounds in human and plant biology, and the biosynthesis of these compounds. Plants synthesize phytochemicals for many reasons, including to protect themselves against insect attacks and plant diseases. The compounds found in plants are of many kinds, but most can be grouped into four major biosynthetic classes: alkaloids, phenylpropanoids, polyketides, and terpenoids.

<span class="mw-page-title-main">Eugenol</span> Chemical compound

Eugenol is an allyl chain-substituted guaiacol, a member of the allylbenzene class of chemical compounds. It is a colorless to pale yellow, aromatic oily liquid extracted from certain essential oils especially from clove, nutmeg, cinnamon, basil and bay leaf. It is present in concentrations of 80–90% in clove bud oil and at 82–88% in clove leaf oil. Eugenol has a pleasant, spicy, clove-like scent. The name is derived from Eugenia caryophyllata, the former Linnean nomenclature term for cloves. The currently accepted name is Syzygium aromaticum.

<i>Monarda</i> Genus of flowering plants

Monarda is a genus of flowering plants in the mint family, Lamiaceae. The genus is endemic to North America. Common names include bergamot, bee balm, horsemint, and oswego tea, the first being inspired by the fragrance of the leaves, which is reminiscent of bergamot orange. The genus was named for the Spanish botanist Nicolás Monardes, who wrote a book in 1574 describing plants of the New World.

Carvacrol, or cymophenol, C6H3(CH3)(OH)C3H7, is a monoterpenoid phenol. It has a characteristic pungent, warm odor of oregano.

<span class="mw-page-title-main">Caryophyllene</span> Chemical compound

Caryophyllene, more formally (−)-β-caryophyllene (BCP), is a natural bicyclic sesquiterpene that is a constituent of many essential oils, especially clove oil, the oil from the stems and flowers of Syzygium aromaticum (cloves), the essential oil of Cannabis sativa, copaiba, rosemary, and hops. It is usually found as a mixture with isocaryophyllene and α-humulene, a ring-opened isomer. Caryophyllene is notable for having a cyclobutane ring, as well as a trans-double bond in a 9-membered ring, both rarities in nature.

<i>Thymus herba-barona</i> Species of herb

Thymus herba-barona is a species of thyme native to Corsica, Sardinia, and Majorca. It is also sometimes known by the common name caraway thyme, as it has a strong scent similar to caraway, for which it can be used as a substitute in any recipe. It can be used in cuisine or as an evergreen ground cover plant for the garden.

<i>Thymus vulgaris</i> Species of flowering plant

Thymus vulgaris is a species of flowering plant in the mint family Lamiaceae, native to southern Europe from the western Mediterranean to southern Italy. Growing to 15–30 cm (6–12 in) tall by 40 cm (16 in) wide, it is a bushy, woody-based evergreen subshrub with small, highly aromatic, grey-green leaves and clusters of purple or pink flowers in early summer.

<span class="mw-page-title-main">Eucalyptus oil</span> Distilled oil from the leaf of Eucalyptus

Eucalyptus oil is the generic name for distilled oil from the leaf of Eucalyptus, a genus of the plant family Myrtaceae native to Australia and cultivated worldwide. Eucalyptus oil has a history of wide application, as a pharmaceutical, antiseptic, repellent, flavouring, fragrance and industrial uses. The leaves of selected Eucalyptus species are steam distilled to extract eucalyptus oil.

<span class="mw-page-title-main">Herbal distillate</span> Aqueous product of the hydrodistillation of volatile organic substances

Herbal distillates, also known as floral waters, hydrosols, hydrolates, herbal waters, and essential waters, are aqueous products of hydrodistillation. They are colloidal suspensions of essential oils as well as water-soluble components obtained by steam distillation or hydrodistillation from plants and herbs. These herbal distillates have uses as flavorings and cosmetics. Common herbal distillates for skincare include rose water, orange flower water, and witch hazel. Rosemary, oregano, and thyme are hydrosols that may be used in food manufacturing.

<i>Monarda fistulosa</i> Species of flowering plant

Monarda fistulosa, the wild bergamot or bee balm, is a wildflower in the mint family Lamiaceae, widespread and abundant as a native plant in much of North America. This plant, with showy summer-blooming pink to lavender flowers, is often used as a honey plant, medicinal plant, and garden ornamental. The species is quite variable, and several subspecies or varieties have been recognized within it.

<i>Thymus pannonicus</i> Species of flowering plant

Thymus pannonicus, known by its common name Hungarian thyme or Eurasian thyme, is a perennial herbaceous plant, distributed in central and eastern Europe and Russia. It grows over open dry meadows, grasslands, and rocks.

<i>Origanum onites</i> Species of plant

Origanum onites, the Cretan oregano, Greek oregano, pot marjoram or Ellinikí rίgani in Greek, is a plant species in the genus Origanum found in Sicily, Greece and Turkey. It has similar flavors as common oregano.It has antimicrobial activities.

2,5-Dimethoxy-<i>p</i>-cymene Chemical compound

2,5-Dimethoxy-p-cymene, or thymohydroquinone dimethyl ether, is a phytochemical found in the essential oils of plants within the family Asteraceae. These essential oils, which contain the compound as a major component of the oil, have antifungal, antibacterial, and insecticidal properties.

<i>Thymus zygis</i> Species of flowering plant

Thymus zygis is a type of flowering plant in the family Lamiaceae native to the Iberian Peninsula and northern Morocco.

<i>Lagoecia</i> Genus of Apiaceae plants

Lagoecia, wild cumin, is a genus of flowering plants in the family Apiaceae. It has only one species, Lagoecia cuminoides, native to the Mediterranean region and as far east as Iran. Its essential oil contains 72.83–94.76% thymol, quite a bit more than thyme itself.

<i>Thymus hyemalis</i> Species of plant in the family Lamiaceae

Thymus hyemalis, the winter thyme, is a species of flowering plant in the family Lamiaceae, endemic to southeast Spain. Its volatile oil constituents vary seasonally.