Thyme oil or thyme essential oil is collected from the Thymus vulgaris herb, which belongs to the Lamiaceae family. Western Mediterranean region is the native place of this plant. European countries have a long history to use different herbal species of the Thymus genus for therapeutic purposes. This herbal plant also grows as a sub-shrub in several Asian countries and North Africa. [1] Folk medicinal application of this herb include expectorant, antihelminthic, carminative, antiseptic, sedative, antioxidative, antispasmodic, antimicrobial, antifungal, antibiotic, and diaphoretic effects. Thyme oil is volatile due to the presence of volatile oil in it. The thyme oil present in Thymus vulgaris usually responsible for its medicinal properties. This oil is added in bath or infusion purposes to cure skin disorders and rheumatic pain symptoms. Presently many cosmetic and food industries added thyme oil in their products for preservative and antioxidant purposes. [2]
Since 1589, thyme oil is used for medicinal purposes. Pharmacopeias and different standard phytotherapy textbooks had mentioned the therapeutic benefits of this herb from many decades ago. Volatile phenolic oil-rich Thyme oil has been enlisted under top 10 essential oil. [1]
Thyme oil is extracted from oval to rectangular shaped fleshy leaves by applying steam distillation process. However, the quality of thyme oil can differ due to selection of the species of thyme, changes in climatic and seasonal conditions, harvesting method, and distillation, and collection process of the oil, etc. Thyme leaves need to separate from their stems and then dry the leaves through a sun-drying process or artificial drying technique. Instead of sun drying, artificial drying technique is a better strategy to obtain consistent product quality. [3]
The essential oil extracted from thyme is a blend of monoterpenes. The oxygenated monoterpenes concentration is higher than the other monoterpenes including monoterpene hydrocarbons, sesquiterpene hydrocarbons, and oxygenated sesquiterpenes. [3]
Thymol and carvacrol are the principle phytochemicals present in thyme oil. [2] Variety of polyphenolic acids like caffeic acid, oleanic acid, rosmarinic acid, and triterpene are present in thyme oil. The phytochemicals present in thyme oil include thymol, borneol, cineol, gerniol, linalool, cymene, limonene, myrcen, pinen, and sabinen. [1]
Each of the phytochemical constituent present in Thyme oil has specific pharmacological properties. Altogether, this combination of phytochemicals provides a great medicinal value of this oil. Following are some phytochemical specific pharmacological properties:
Thymol: Antioxidant, antibacterial, antifungal and antiseptic properties.
Carvacrol: Anti-inflammatory, antithrombotic, antimicrobial, acetylcholinesterase inhibitor properties.
Linalool: Analgesic, anti-nociceptive, anti-inflammatory, antioxidant, and antiviral effect.
Apigenin: Anti-inflammatory, anti-oxidant, antiprogression, anti-carcinogenic, and anti-viral properties.
Eugenol: Anti-anaphylactic, neuro-protective, anti-bacterial and anticancer activities
Rosmarinic acid: Anti-mutagen, anti-allergic, astringent, anti-inflammatory and antioxidative. [4]
Animal research study has reported that treatment with thyme oil for 4 weeks reduces the lipid peroxidation levels in hepatic and renal cells. It also improves antioxidant enzyme activity in the liver. Thyme oil supplementation helps to maintain a higher level of polyunsaturated fatty acid levels in brain, heart, kidney and liver tissue.
Thymol and carvacol present in thyme oil provide anti-inflammatory property. It has been found in an in-vivo research study that application of thyme oil accelerates the wound healing property by reducing the leukocytes influx into the injured area. Both chronic and acute inflammatory conditions including edema and skin damage can be effectively controlled by using thyme oil.
Great respiratory benefits obtain from thyme oil due to its smooth muscle relaxing property and it prevents phasic contraction of the muscles present in the pharynx. The muscle relaxation of thyme oil obtained by involving muscarinic receptors, and also acts as an antagonist of calcium channel and open the potassium channel.
Phenolic compounds present in thyme oil acts as GABAA receptor. Whereas, carvacol acts as a transient receptor potential (TRP) V3 channel agonist. Thus, thyme oil interacts with the neuronal process.
Both sedative and mood-elevating effect of thyme oil obtained by adjusting the bioactive phytochemical constituents present in thyme oil. The carvacol can modulate GABA-ergic transmission, and also acts as a selective serotonin reuptake inhibitor.
The gastrointestinal benefits obtain from thyme oil due to its active constituent thymol can improve intestinal homeostasis by contacting with chemical receptor present in it. Thyme oil modifies the microbiome of the GI tract. [5]
There are different dosage forms are available in the market containing thyme oil to treat a variety of disease condition naturally.
Apart from these, Thyme oil can be used as insect replant and added in different cosmetic preparation like shampoo, foot cream, etc.
In traditional medicine, thyme oil has a wide application due to its broad range of therapeutic actions. Following are some effective use of this natural ingredient:
Treat infectious disease
The broad antimicrobial property of thyme oil is effective to control both bacterial and fungal growth and treat the associated infections. Certain bacterial infections caused by E. coli, E. faecalis, K. pneumonia, P. aeruginosa, and S. aureus can effectively treat with thyme oil remedy. Fungi like C. albicans and S. typhimurium infections also subsided by this herbal remedy.
The antimicrobial property of the thyme oil effective to treat infection occurs in the oral cavity, respiratory and genitourinary tracts. It also acts as an anthelmintic and reduces parasitic intestinal worm growth.
Improve respiratory condition
It has antispasmodic property by relaxing the smooth muscle, which is effective to control asthma and chest congestion. Antimicrobial property and anti-inflammatory activity help to give relief from cold and cough attack. It also acts as anti-tussive, which controls the cough frequency and helps to prevent exaggerated condition at night. The sedative effect of this oil helps to take rest at night and imparts physical rest to heal up the condition.
Skin health improvement
Cosmetic industries have started to manufacture thyme oil-containing antiseptic cream, ointment to treat burns, wounds, acne, cuts, scars, etc. Also, thyme oil is a good remedy for different skin conditions like eczema, skin burn condition, dry, itchy skin. The skin healing property of thyme oil obtains due to its anti-inflammatory, antioxidant and antimicrobial properties. It has good bug repellant property and safe to apply on skin.
Oral health conditions
Multiple microbial growths in oral cavity often cause tooth decay. Thyme oil treatment is one solution for multiple oral conditions due to its antiseptic and antimicrobial property. It helps to eliminate bad breath, natural treatment for gum disease and vanishes the scope of tooth decay.
Cardiac health
Thyme oil improves blood circulation and also relaxes arteries and veins. These benefits help to support cardiac functioning by normalizing blood flow and reduce the risk of hypertension.
Anxiolytic
Thyme oil has sedative property as well as acts as an antidepressant by acting a selective serotonin reuptake inhibitor. It also elevates mood by regulating GABA-ergic transmission. All these properties help to provide mental relaxation. [8]
Thyme oil is a relatively safe natural medicinal agent. It does not cause any side effect and safe to use within the limited dose for both adult and children. Excessive dose exposure can cause a burning sensation, skin itching, etc. Detail toxicology study requires to conduct for future application. There is no study specifically access the side effect burden of thyme oil among pregnant and lactating mother.