The Benefits of Eucalyptus

by Mike August 14, 2011

Eucalyptus is a diverse genus of flowering trees (and a few shrubs) in the myrtle family, Myrtaceae.

Members of the genus dominate the tree flora of Australia. There are more than 700 species of Eucalyptus, mostly native to Australia, and a very small number are found in adjacent areas of New Guinea and Indonesia and one, Eucalyptus deglupta, ranges north to the Philippines. Only 15 species occur outside Australia, and only 9 do not occur in Australia. Species of Eucalyptus are cultivated throughout the tropics and subtropics including the Americas, Europe, Africa, the Mediterranean Basin, the Middle East, China and the Indian Subcontinent.

Eucalyptus is one of three similar genera that are commonly referred to as "eucalypts," the others being Corymbia and Angophora. Many, but far from all, are known as gum trees because many species exude copious sap from any break in the bark (e.g. Scribbly Gum). The generic name is derived from the Greek words (eu), meaning "well," and (kalyptos), meaning well "covered," which refers to the operculum on the calyx that initially conceals the flower.

Some Eucalyptus species have attracted attention from global development researchers and environmentalists. Such species have desirable traits such as being fast-growing sources of wood, producing oil that can be used for cleaning and functions as a natural insecticide, or an ability to be used to drain swamps and thereby reduce the risk of malaria. Outside their natural ranges, eucalypts are both lauded for their beneficial economic impact on poor populations and derided for being invasive water-suckers, leading to controversy over their total impact.

Eucalyptus oil:

Eucalyptus oil is readily steam distilled from the leaves and can be used for cleaning, deodorizing, and in very small quantities in food supplements, especially sweets, drops, toothpaste and decongestants. It also has insect repellent properties (Jahn 1991 a, b; 1992), and is an active ingredient in some commercial mosquito repellents (Fradin & Day 2002).

Honey:

The nectar of some eucalypts produces high-quality monofloral honey.

Music instrument:

Eucalypt wood is also commonly used to make didgeridoos, a traditional Australian Aboriginal wind instrument. The trunk of the tree is hollowed out by termites, and then cut down if the bore is of the correct size and shape.

Dye:

All parts of Eucalyptus may be used to make dyes that are substantive on protein fibers (such as silk and wool), simply by processing the plant part with water. Colors to be achieved can range from yellow and orange through green, tan, chocolate and deep rust red. The material remaining after processing can be safely used as mulch or fertilizer.

Habitat:

Australia, North and South Africa, India, and Southern Europe.

The tree is indigenous with a few exceptions to Australia and Tasmania. The genus contains about 300 species and is one of the most characteristic genera of the Australian flora.

Description:

The leaves are leathery in texture, hang obliquely or vertically, and are studded with glands containing a fragrant volatile oil. The flowers in bud are covered with a cup-like membrane (whence the name of the genus, derived from the Greek eucalyptos well-covered), which is thrown off as a lid when the flower expands. The fruit is surrounded by a woody, cupshaped receptacle and contains numerous minute seeds.

Eucalyptus trees are quick growers and many species reach a great height. Eucalyptus amygdalin (Labille ) is the tallest known tree, specimens attaining as much as 480 feet, exceeding in height even the Californian Big Tree (Sequoia gigantea). Many species yield valuable timber, others oils, kino, etc.

There are a great number of species of Eucalyptus trees yielding essential oils, the foliage of some being more odorous than that of others, and the oils from the various species differing widely in character. It necessarily follows that the term Eucalyptus oil is meaningless from a scientific point of view unless the species from which it is derived is stated.

The Eucalyptus industry is becoming of economic importance to Australia, especially in New South Wales and Victoria. Many of the old species which give the oil of commerce have given way to other species which have been found to gave larger yields or better oils. About twenty-five species are at the present time being utilized for their oil.

The oils may be roughly divided into three classes of commercial importance:

(1) the medicinal oils, which contain substantial amounts of eucalyptol (also known as cineol); (2) the industrial oils, containing terpenes, which are used for flotation purposes in mining operations; (3) the aromatic oils, such as E. citriodora, which are characterized by their aroma.

The British Pharmacopoeia describes Eucalyptus Oil as the oil distilled from the fresh leaves of E. globulus and other species.

E. globulus, the best-known variety (its name bestowed, it is said, by the French botanist De Labillardière, on account of the resemblance of its waxy fruit to a kind of button at that time worn in France), is the Blue Gum Tree of Victoria and Tasmania, where it attains a height of 375 feet, ranking as one of the largest trees in the world. It is also called the Fever Tree, being largely cultivated in unhealthy, low-lying or swampy districts for its antiseptic qualities.

The first leaves are broad, without stalks, of a shining whitish-green and are opposite and horizontal, but after four or five years these are succeeded by others of a more ensiform or sword-shaped form, 6 to 12 inches long, bluish-green in hue, which are alternate and vertical, i.e. with the edges turned towards the sky and earth, an arrangement more suited to the climate and productive of peculiar effects of light and shade. The flowers are single or in clusters, almost stalk less.

The Eucalyptus, especially E. globulus, has been successfully introduced into the south of Europe, Algeria, Egypt, Tahiti, South Africa and India, and has been extensively planted in California and also, with the object of lessening liability to droughts, along the line of the Central Pacific Railway.

It thrives in any situation, having a mean annual temperature not below 60 degrees F., but will not endure a temperature of less than 27 degrees F

Constituents:

The essential Oil of Eucalyptus used in medicine is obtained by aqueous distillation of the fresh leaves. It is a colorless or straw-colored fluid when properly prepared, with a characteristic odor and taste, soluble in its own weight of alcohol. The most important constituent is Eucalyptol, present in E. globulus up to 70 per cent of its volume. It consists chiefly of a terpene and a cymene. Eucalyptus Oil contains also, after exposure to the air, a crystallizable resin, derived from Eucalyptol.

The British Pharmacopoeia requires Eucalyptus Oil to contain not less than 55 per cent, by volume, of Eucalyptol, to have a specific gravity 0.910 to 0.930 and optical rotation -10 degrees to 10 degrees. The official method for the determination of the Eucalyptol depends on the conversion of this body into a crystalline phosphate, but numerous other methods have been suggested (see Parry, Essential Oils,

A small amount of medicinal oil is still distilled from E. globulus, but Its odour is less agreeable than those of many others. Today, E. polybractea (Silver Malee Scrub which is cultivated and the oil distilled near Bendigo in Victoria), containing 85 per cent of Eucalyptol, and E. Smithii (Gully Ash) are favourites for distillation. Among others frequently employed, E. Australiana yields valuable medicinal oil and also E. Bakeri, a large shrub or pendulous willow-like tree, about 30 to 50 feet high, with very narrow leaves, found from northern New South Wales to central Queensland, known locally as the 'Malee Box.' The oil from this species is of a bright reddish-yellow and contains 70 to 77 per cent of Eucalyptol and other aromatic substances identical with those found in E. polybractea.

The oil used for flotation purposes in the extraction of ores is known as that of E. amygdalina, and is probably derived from this tree as well as from E. dives. It is an oil containing little Eucalyptol and having a specific gravity from 0.866 to 0.885, and an optical rotation -59 to -75 degrees, its chief constituent is phellandrene, which forms a crystalline nitrate and is very irritating when inhaled. There is a considerable demand in New South Wales for the cheap phellandrene Eucalyptus oils for use in the mining industry in the separation of metallic sulphides from ores.

Of the perfume-bearing oils, that of E. citriodora, the CITRON-SCENTED GUM, whose leaves emit a delightful lemon scent, contains up to 98 per cent of citronellol and is much used in perfumery, fetching four times as much as the medicinal oils. E. Macarthurii ('Paddy River Box') contains up to 75 per cent of geranyl acetate, and as a source of geraniol this tree would probably repay cultivation: it is now receiving special attention in Australia, as it is a very rapid grower. E. odorata yields also odorous oil used by soap makers in Australia. E. Staigeriana, the Lemon-scented Iron Bark, has also a very pleasing scent, and the fragrance of the leaves of E. Sturtiana is similar to that of ripe apples.

There are a number of Eucalypts which contain a ketone known as piperitone, such as E. piperita. This body can be used in the synthesis of menthol, but it remains to be seen whether the process can be made a commercial success. E. dives (Peppermint Gum) and E. radiata (White Top Peppermint) yield oils with a strong peppermint flavour.

Details of an enormous number of the oils of Eucalyptus can be found in A Research on the Eucalypts, by Baker and Smith.

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.

Types and production:

Eucalyptus oil in the trade are categorized into three broad types according to their composition and main end-use: medicinal, perfumery and industrial. The most prevalent is the standard cineole based "oil of eucalyptus", a colourless mobile liquid (yellow with age) with a penetrating, camphoraceous, woody-sweet scent.

China produces about 75% of the world trade, but most of this is derived from camphor oil fractions rather than being true eucalyptus oil.[2] Significant producers of true eucalyptus oil include South Africa, Portugal, Spain, Brazil, Australia, Chile and Swaziland.

Global production is dominated by Eucalyptus globulus. However, Eucalyptus kochii and Eucalyptus polybractea have the highest cineole content, ranging from 80-95%. The British Pharmacopoeia states that the oil must have a minimum cineole content of 70% if it is pharmaceutical grade. Rectification is used to bring lower grade oils up to the high cineole standard required. Global annual production of eucalyptus oil is estimated at 3,000 tones.

The eucalyptus genus also produces non-cineole oils, including piperitone, phellandrene, citral, methyl cinnamate and geranyl acetate.

Eucalyptus oil should not be confused with the term "eucalyptol", another name for cineole.

Uses:

Medicinal and antiseptic:

The cineole-based oil is used as component in pharmaceutical preparations to relieve the symptoms of influenza and colds, in products like cough sweets, lozenges, ointments and inhalants. Eucalyptus oil has antibacterial effects on pathogenic bacteria in the respiratory tract. Inhaled eucalyptus oil vapor is a decongestant and treatment for bronchitis. Cineole controls airway mucus hyper secretion and asthma via anti-inflammatory cytokine inhibition.

Eucalyptus oil also stimulates immune system response by effects on the phagocytic ability of human monocyte derived macrophages.

Eucalyptus oil also has anti-inflammatory and analgesic qualities as a topically applied liniment ingredient.

Eucalyptus oil is also used in personal hygiene products for antimicrobial properties in dental care and soaps. It can also be applied to wounds to prevent infection.

Repellent and biopesticide:

Cineole based eucalyptus oil is used as an insect repellent and biopesticide. In the U.S., eucalyptus oil was first registered in 1948 as an insecticide and miticide.

Flavoring:

Eucalyptus oil is used in flavoring. Cineole based eucalyptus oil is used as a flavoring at low levels (0.002%) in various products, including baked goods, confectionery, meat products and beverages. Eucalyptus oil has antimicrobial activity against a broad range of food borne human pathogens and food spoilage microorganisms. Non-cineole gum, strawberry and lemon ironbark are also used as flavoring.

Fragrance:

Eucalyptus oil is also used as a fragrance component to impart a fresh and clean aroma in soaps, detergents, lotions and perfumes.

Skin Care:

Organic certified eucalyptus Extract is a natural products for skin care, used for is anti oxidant and anti aging properties in skin care products. As a natural component of organic skin care, anti wrinkle, natural anti aging, miracle lift. Also sometime found as a fragrance material in organic and natural skin care.

Industrial:

Research shows that cineole based eucalyptus oil (5% of mixture) prevents the separation problem with ethanol and petrol fuel blends. Eucalyptus oil also has a respectable octane rating and can be used as a fuel in its own right. However, production costs are currently too high to be economically viable as a fuel.

Phellandrene and piperitone based eucalyptus oils have been used in mining to separate metallic sulphides via flotation.

Safety and toxicity:

If consumed internally at low dosage as a flavoring component or in pharmaceutical products at the recommended rate, cineole based 'oil of eucalyptus' is safe for adults. However, systemic toxicity can result from ingestion or topical application at higher than recommended doses.

The probable lethal dose of pure eucalyptus oil for an adult is in the range of 0.05 mL to 0.5 mL/per kg of body weight. Because of their high body surface area to mass ratio, children are more vulnerable to poisons absorbed transdermally. Severe poisoning has occurred in children after ingestion of 4 mL to 5 mL of eucalyptus oil.

History:

Australian Aboriginals use eucalyptus leaf infusions - whereby eucalyptus oil is a fraction - as a traditional medicine for treating body pains, sinus congestion, fever, and colds.

Dennis Considen and John White, surgeons on the First Fleet, distilled eucalyptus oil from Eucalyptus piperita found growing on the shores of Port Jackson in 1788 to treat convicts and marines. Eucalyptus oil was subsequently extracted by early colonialists, but was not commercially exploited for some time.

Baron Ferdinand von Mueller, Victorian botanist, promoted the qualities of Eucalyptus as a disinfectant in "fever districts", and also encouraged Joseph Bosisto, a Melbourne pharmacist, to investigate the commercial potential of the oil. Bosisto started the commercial eucalyptus oil industry in 1852 near Dandenong, Victoria, Australia, when he set-up a distillation plant and extracted the essential oil from the cineole chemo type of Eucalyptus radiata. This resulted in the cineole chemotype becoming the generic 'oil of eucalyptus', and "Bosisto's Eucalyptus Oil" still survives as a brand.

French chemist, F.S. Cloez, identified and ascribed the name eucalyptol - also known as cineole - to the dominant portion of E. globulus oil. By the 1870s oil from Eucalyptus globulus, Tasmanian blue gum was being exported worldwide and eventually dominated world trade, while other higher quality species were also being distilled to a lesser extent. Surgeons were using eucalyptus oil as an antiseptic during surgery by the 1880s.

The Australian eucalyptus oil industry peaked in the 1940s, the main area of production being the central goldfields region of Victoria, particularly Inglewood; then the global establishment of eucalyptus plantations for timber resulted in increased volumes of eucalyptus oil as a plantation by-product. By the 1950s the cost of producing eucalyptus oil in Australia had increased so much that it could not compete against cheaper Spanish and Portuguese oils. Non-Australian sources now dominate commercial eucalyptus oil supply, although Australia continues to produce high grade oils, mainly from blue mallee (E. polybractea) stands.

More Information:

http://theskinsociety.com/support/skin-care-glossary.html