 Tea Tree Melaleuca alternifolia (Maiden & Betche) Cheel – Myrtaceae (myrtle) Family
Synonyms: Ti-tree, ti-trol, narrow-leaved paperbark tea, melasol Parts Used: Leaves and branch tips Harvest Season: Throughout the growing season. Botanical Description: Tea tree is a small tree growing up to 25 feet in height in its native habitat. It has distinctive papery bark. The leaves are narrow and arranged in three’s along the stem. The flowers are usually creamy-white though sometimes yellow-tinted. The seed is a small woody capsule which germinates relatively poorly. There are over 200 species of Melaleuca that grow mainly in Australia, with a few growing in Southeast Asia. Two other species that are distilled for their oils are Melaleuca cajuputi and Melaleuca quinquenervia. Origin: All tea tree oil comes from eastern Australia. It was first distilled in 1924 and the first plantation was planted in 1975. Growing Conditions: Tea tree prefers a wet, swampy soil. It can be cultivated in a variety of conditions however, and on plantations it grows with or without irrigation (though irrigation usually yields more oil). Oil content varies tremendously, even from day to day. Adequate moisture is a factor, but other unknown factors seem to affect the oil content as well. The plant is frost-sensitive. To harvest, the tree is cut down, but within 18 months it is ready to harvest again because the stump sprouts and grows quickly. Extraction Method: Steam distillation of the leaves and twigs. Yield: Varies tremendously from 1-4% with an average closer to 1%. Oil Characteristics: The oil is clear, colorless to pale yellow. It has a spicy, medicinal aroma. Aroma Profile: Top Note: strong, powerful, camphoraceous-cineolic, oily Middle Note: diffusive, mace-like Dry-out: weak, dry, mace-like Major Constituents: Terpinen-4-ol (>30%), 1,8-cineole (1 to 15%), α-pinene (6%), p-cymene, limonene, α-terpinene, α-terpineol, aromadendrene, γ-terpineol, sabinene, γ-terpineol, δ-cadinene. History: The aborigines of Australia used the leaves for inhalation and to make a tea to relieve colds and headaches. The name tea tree comes from Captain Cook, who in 1777 brewed the tea to prevent scurvy. It was first distilled in 1924 and was used extensively in World War II. It was first cultivated in 1975, and today virtually all of the tea tree oil comes from plantations. It is the second best selling oil in North America. Aromatherapy Benefits: Purifying, uplifting, cleansing. It is generally a safe oil to apply to the skin, and its anti-microbial action is used for many purposes. It is well known as a gargle, used in numerous facial formulas and in various applications to minor scraps and cuts. Clinical Studies: Tea tree is one of the most studied oils in the world. It has been shown in numerous studies to be anti-bacterial and anti-fungal (1,2,3). It has clearly been shown to inhibit candida and thus it has potential in the topical treatment of superficial candida infections (2). The oil has also shown promise in toenail fungus and was shown in one trial to be as effective as clotrimazole (1). Cosmetic Uses: Tea tree is used in a variety of skin care products, but almost exclusively for its antimicrobial actions. It blends well with spicy oils like nutmeg, clove, rosemary, marjoram and thyme as well as woody oils like cedarwood and pine. Like many oils, it seems to blend well with lavender. Safety: Tea tree oil is considered non-toxic and non-irritating. While also considered non-sensitizing, some individuals do seem to be sensitive to it. Researchers have found that one component of the oil, para-cymene, increases dramatically as the oil oxidizes. This occurs much more rapidly when the oil was stored in clear bottles. In dark bottles the content of para-cymene did not change during the trial. Para-cymene is a known skin irritant and may account for the skin sensitively experienced by some people, especially if using oxidized oil. For this reason, the oil should stored in an air-tight bottle away from light and heat. Quality Issues: Tea tree is rarely adulterated, though there is a lot of variation in constituents of the oil due to several environmental factors. Regulatory Status: GRAS 182.20 Tim’s Notes: Tea tree is a safe and easy to use oil. It is effective against a wide variety of conditions and thus is one of the top oils in my first aid kit. I once used the oil on an airplane to disinfect my air space and the airplane attendant suddenly shouted, ‘what’s that, something’s wrong, what’s that smell?’ I immediately informed her that it was just little old me and that nothing was wrong. When she smelled the bottle she immediately said, ‘yuck’. My suggestion would be not to use it on a plane but stick with a more common oil like lavender. It is perhaps the only oil that is available today in suppositories. References -
Buck DS et al. Comparison of two torpical preparations for the treatment of onychomycosis: Melaleuca alternafolia oil and clotrimozole. Journal of Family Practice, 1994;38(6): 601-605. Cited in Australian Tea Tree by C. Dean, The 2nd Australasian Aromatherapy Conference Proceedings, Australia, 1998. -
Hammer KA et al. In vitro activity of essential oils, in particular Melaleuca alternafolia oil and Tea Tree Oil against Candida spp. Journal of Antimicrobial Chemotherapy. 1998; 42(5): 591-595. Cited in Australian Tea Tree by C. Dean, The 2nd Australasian Aromatherapy Conference Proceedings, Australia, 1998. -
Carson CF et al. In vitro activity of the essential oil Melaleuca alternafolia against Streptococcus spp. Journal of Antimicrobial Chemotherapy. 1996; 37(6): 1177-1181. Cited in Australian Tea Tree by C. Dean. The 2nd Australasian Aromatherapy Conference Proceedings, Australia, 1998. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
| 