Mānuka Oil (Leptospermum scoparium)
By Hwaa Irfan
The name Mānuka is a Māori word that provides a distinctive name for a plant that has wider human usage medicinally speaking than its common reference, ‘tea tree’ of Australia. Mānuka honey is becoming increasingly popular because of its medicinal properties which are utilized by the pharmaceutical industry. The fresh pungent leaves were made popular by Captain Cook as they make a good cup of tea, but to get the best out of the leaves, they should be brewed longer in order to release the flavor. Therapeutically, the Maori of New Zealand use various parts of Leptospermum s. for a wide variety of complaints, from moral to medicinal with an 800 year history of use.
There are 85 species to be found. A member of the Myrtaceae family of the plant kingdom, the same family as eucalyptus, Leptospermum scoparium is an evergreen small tree/shrub that is native to New Zealand and southeast Australia, but can be found in places like Hawai’i, and Brazil.
The wood of Leptospermum s. is hardy and has been used to make tools, and sawdust to smoke meat and fish due to the flavor it adds.
With a preference for dry, clear well drained areas, Leptospermum s. can be found in rocky, sandy soil, light (sandy), medium (loamy) and heavy (clay) soils. However it does poorly in the shade, and is intolerant of strong inland winds, but not sea winds. Ecologically they make good nursery crops for re-forestation.
They produce a dense bush of small leaves with short spiny tips making them prickly. The 5-petaled flowers range from white, to rose pink. They are hermaphrodite (both male and female organs) and are pollinated by Insects. They tend to flower from September to February with peak flowering from November to January.
The oils extracted from the crushed foliage of Mānuka contain an antibiotic agent called leptospermone which is claimed to have many medicinal properties. The essential is extracted from the oil saps in the leaves/ small branches through steam distillation.
When buying, look out for the scent, a honey-like aroma. The color of the oil can vary from colorless – yellow depending on the specie. The best variety is from New Zealand where it grows wild, and not for commercial production, which guarantees quality so expect a high price.
Please note that the content of the following properties will vary from specie to specie, and that the properties are stronger amongst naturally growing species:
- β -myrcene
- β-pinene (higher in content in the far north of New Zealand)
- caryophyllene oxide
- cinnamyl acetate
- citronellyl acetate
- germacrene B and D
- geranyl acetate
- methyl geranate
- Rose oxide
- Sesquiterpene hydrocarbons
- Trichetones (present in the varieties in East Cape and Marlborough Sounds, New Zealand, and Brazil)
Limonene is the source of the smell of the oil. Limonene has anti-cancerous effects, and increases the enzymes of the liver concerned with detoxification. D-limonene has been used clinically to dissolve cholesterol-containing gallstones.
Linalool decreases aggressive behavior, stress, and improves sleep
Terpinen-4-ol, which is found in another member of the Myrtaceae family, eucalyptus has strong germicidal properties.
Trichetones determine the level of antimicrobial activity in Leptospermum s.
It must be noted that in modern pharmaceutics, an antibacterial kills all bacteria, including good and much needed bacteria, whereas in plant-based natural remedies, specific bacteria are targeted. Oil of Leptospermum s. has proven effective in laboratory tests against 39 micro-organisms!
Some of the therapeutic properties are as follows:
- Anti allergenic
- Anti bacterial
- Anti fungal
- Anti inflammatory
- Anti histaminic
- Stimulant (immune system)
The antibacterial/antifungal activity of Leptospermum s. has proven effective at targeting Helicobacter pylori,Staphylococcus aureas, Staphylococcus aureas methacillin resistant, Staphylococcus epidermidis, Streptococcus faecalis, Streptococcus agalactiae, Micrococcus luteus, Sarcina lutea, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Proteus vulgaris, Vibrio furnissii, Pseudomonas aeruginosa, Pseudomonas fluorscens, Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum canis, Aspergillus niger, and Candida albicans.
As an analgesic reduces pain associated with cold, fever, inflammation, exertion of muscles, toothache, headache etc.
As an antiseptic it is good for external and internal wounds
As an antiviral helps to cure viral infections
As an antibacterial kills bacteria from food poisoning, typhoid, malaria, colic, and bacterial infections in the colon, digestive system, and urinary tract
As a digestive stimulates secretion of gastric juices, acids and bile Its aroma also
As an expectorant relieves catarrh and congestion of nasal tract, larynx, pharynx, bronchi and lungs due to cold and viral infection.
As a fungicidal prevents growth of fungus, helps to clear fungal infections, and related skin diseases. , most of which are caused due to fungal infections. It also helps to cure dysentery.
As a sedative induces calm, relieves nervous stress and anxiety. It also gives a happy feeling in cases of anger or sadness.
As a stimulant improves peristalsis of the intestines thus aiding digestion – the intestines are 80% of the immune system
As a nervine strengthens the nervous system
As a vulnerary promotes quick healing of wounds, external or internal, and protects against infection
For glossary see It All Makes Good Scents!
It is contraindicated if on medication that includes ofloxacin, enoxacin, and sparfloxacin. It is also contraindicated for pregnant women due to the plants spasmolytic properties.
The oil can only be used for external use, though some traditions have specific applications for internal use. It is preferable to dilute it at 3 drops per tablespoon. (see Carrier Oils)
Digestive – Indigestion, sluggish, stomach upsets
Gender – Low libido, vaginitis
Head – Dandruff, Gingivitis, mouth ulcers, rhinitis, Tinea, Tonsillitis
Mind –Anxiety, stress, oversensitive nervous system, negative external influences, passivity, strengthens the psyche
Musculoskeletal – Muscular tension, sprains, stiff joints, rheumatism,varicose
Nervous – Nervous tension
Respiratory – Asthma, coughs (including whooping cough), colds, flu, hayfever
Skin – Abrasions, abcesses, acne, bed sores, blisters, boils, burns, carbuncles, cold sores, cracked skin, dandruff, dermatitis, eczema, fungal infections, impetigo, insect bites, leeches, lice, psoriasis, ringworm, oily, ulcers, warts
Diffuser – To fumigate a space/home
Vapor therapy – 1 drop in water for colds, decision-making, depression, fatigue, stress, lack of energy, low spirits, poor concentration, sluggish digestion, upper respiratory tract infections.
Bath – external – 2-4 drops in the bath before adding water. As a deodorant, wash daily, and 2 drops to a cream and apply for the feet, 3x weekly.
Massage – Scalp – Add 10 drops to shampoo applied to wet hair. For sunburns after applying cold water to reduce heat, a couple drops of oil in natural cream rubbed into sunburnt area.
Neat – fungal infections – a couple of drops on cotton-wool applied twice daily. Add to 2-4 drops to a natural cream/lotion for skin complaints
Demuner, A.J. et al. “Seasonal Variation in the Chemical Composition and Antimicrobial Activity of Volatile Oils of Three Species of Leptospermum (Myrtaceae) Grown in Brazil.” Molecules 2011, 16, 1181-1191; doi:10.3390/molecules16021181
Forst, J.R. “Leptospermum scoparium.” http://www.pfaf.org/user/Plant.aspx?LatinName=Leptospermum+scoparium
“Manuka Oil Uses and Information.” http://www.manukaoil.co.nz/manuka_oil_uses.htm