Myrtaceae are mainly trees and shrubs from warm and temperate regions; many are aromatic.
Among the 3000 species of myrtaceae, the genus eucalyptus contains at least 600.
They are trees or shrubs with evergreen foliage and often with bark that exfoliates and falls to shreds.
Endemic to Australia and Tasmania, they are also present in eastern Malaysia.
Some eucalyptus trees are giant, the largest in the world, up to 150 m high and 10 m in diameter at their base.
Many species have been successfully introduced in most tropical and warm temperate regions.
For example E. globulus in Europe (Spain, Italy,Portugal), but also in Brazil and North, West and South Africa.
E. citriodora in Java, Seychelles, Africa, Brazil and tropical America.
In some cases these myrtaceae can become invasive and be considered as plant pests (example melaleuca in the "everglades" in Florida)
They are also ornamental trees, with a very fast growth (pulp, reforestation), source of pollen and nectar for bees.
In Australia the native species from which essential oils are extracted are mainly:
Each species of Eucalyptus can contain essential oils whose composition is variable or even completely different, these are the "chemotypes".
The commonly known essential oil of eucalyptus can come from several species, it must contain mainly "eucalyptol" or 1-8 cineole and it comes often from Eucalyptus globulus or Eucalyptus radiata.
A "good" eucalyptus essential oil must come from a chemotyped species and contain at least 60-70% eucalyptol (1-8 cineole).
Some essential oils contain up to 90%.
They can be chemically rectified essential oils (to increase the percentage of eucalyptol) and even in the worst case a completely synthetic product.
CHEMICAL COMPOSITION AND PROPERTIES
The dried leaf and EO (essential oil) of eucalytus (mainly E. Globulus and E. radiata) are part of the French pharmacopoeia.
The leaf EO content varies between 0.5 and 3.5%, eucalyptol (1-8 cineole) is the major constituent (60 to 80%):
- there are also other terpene compounds (euglobols),
- phenolic compounds,
- flavonoids (rutoside, hyperoside) and wax.
Eucalyptus essential oil is:
- antiseptic in vitro (but less than thymol, terpineol or eugenol EO),
- neurotoxic (epileptogenic) at high dose (LD 50 = 1.7 ml / kg in the rat in IP),
- at a lower dose, some digestive disorders, hypotension and mental confusion,
- at the usual therapeutic doses (0.05 to 0.2 ml / day) no toxic risk.
Eucalyptol is absorbed through the digestive, cutaneous or rectal routes and eliminated by respiratory and renal routes.
There is activation of the ciliary movements of the bronchial epithelium with an EXPECTORANT AND MUCOLYTIC ACTION on the bronchial secretions.
E. globulus leaves would be HYPOGLYCEMIC.
Other Eucalyptus have very different composition of EOs, including:
E. citriodora, 65 to 85% citronellal used in perfumery,
E. dives,EO with piperitone , chemical source for the synthesis of thymol and menthol,
E. macarturi, EO with geraniol.
In aromatherapy, Eucalyptus EO is very often prescribed in combination with other antiseptic EOs in upper respiratory diseases :
- "flu" banal or superinfected,
EXAMPLES OF MEDIUM DOSAGE
oral: 2 to 3 drops of EO on a piece of bread, in milk or honey 3 times a day,
or more classically: 1 to 2 g of HE in 125ml of alcohol at 90 ° 30 drops 3 times a day,
rectally: enema, EO 5g in 125 ml of sweet almond oil,
Inhalation: a few drops of Eucalyptus EO or a mixture of EO with bronchopulmonary aim in a bowl of hot water, breathe for a few minutes under a towel. 2 to 3 times a day.
In thoracic friction: 10 g HE in 20 g of glycerin and 100 ml of alcohol at 70-90 °;
Eucalyptus EO is sometimes associated in these preparations with EO of pine, lavender, thyme, cinnamon.
The hoeopathic tincture or the alcoholic tincture of eucalyptus leaves (Globulus or radiata) has the same indications, average dose: 50 to 150 drops per day; they would be slightly hypoglycemic .
Many preparations containing eucalyptol are found in pharmacy: syrups, pastes or lozenges, nasal drops, liquid for inhalation and many bronchopulmonary drugs.
EUCALYPTUS LEAVES (Globulus or radiata))
The eucalytus leaf is used in the composition of phytomedicines used to treat acute bronchial infections and infectious complications of influenza.
INFUSION : a teaspoon of broken dry leaves in a cup of hot water, 10 minutes of infusion, 3 to 5 cups a day.
This infusion is also febrifuge and eupeptic ( but in some people it cuts the appetite).
In external use Eucalyptus EO and prolonged infusion of leaves are slightly antiseptic and healing: wounds, burns, leucorrho
CHEMICAL COMPOSITION AND PROPERTIES
The NEOCALEDONIAN NIAOULI EO (chemotype 2 eucalyptol and terpineol) purified and modified, is the "GOMENOL" (from GOMEN a city of New Caledonia), with composition similar to that of eucalyptus: eucalyptol 45 to 65 % with pinene, limonene and alpha terpineol.
CAJEPUT EO is also of similar composition.
The Australian TEA TREE has a slightly different and variable composition; according to the varieties, the EO contains up to 40% of terpineol (powerful antiseptic), for others eucalyptol dominates (up to 60%), one also finds pinene and limonene. See also phytomania.com/tea-tree.htm
All of these oils are potently bactericidal in vitro and cajeput HE would be stimulating and mildly parasympathicolytic
These EOs are eliminated in urine and breath after digestive absorption and are therefore recommended in respiratory infections (niaouli) and urinary (cajeput.)
For example :
cystitis, urethritis, orchiepididymites: EO cajeput
1 to 2 g in 125 ml of alcohol at 90 °, 40 drops 3 times a day,
complicated flu, bronchitis: EO niaouli, EO cajeput,
1.5 g in 90 ml of alcohol at 90 °, 30 drops 3 times a day.
Or just 2 to 3 drops of EO of Niaouli (respiratory infections) or Cajeput (infection-urinary inflammation) on bread or in honey or milk 2 to 3 times a day
EO niaouli is found in many bronchopulmonary specialties and niaouli leaf in some phytomedicines.
In dermatology: infected wounds, minor skin infections, EO of TEA-TREE M. alternifolia (5g in 100ml of alcohol at 90 °) powerfully bactericidal by its content in terpineol.
Myrtle from the Mediterranean region is one of the few relics of the distant age when tropical flora extended to latitudes 40-50 N.
It is a shrub 1 to 3 m high, fragrant, with oval or lanceolate leaves, smooth, shiny and leathery, small (2 to 4 cm).
The solitary flowers are white or tinged with red, the fruit is black with blue reflections.
Widely used until the 18th century, it is now a little forgotten..
CHEMICAL COMPOSITION AND PROPERTIES
Its EO contains many terpenoids : camphene, myrtenol, nerol and also geraniol and eucalyptol (cineole).
The myrtle is rich in tannins and contains 0.3 to 0.5% essential oil, so it is an astringent , antiseptic and similar to eucalyptus.
Inhalation , its EO is useful in bronchial infections and upper respiratory tract infections .
The infusion of berries has the same indications: 15 to 20 g of berries per liter of water, 2 to 3 cups per day.
It can also be recommended in urinary tract infections.
Traditionally, leaf infusion (30 g per liter of water) is useful for treating dry eczema and psoriasis, ulcers and wounds (antiseptic healing).
EUCALYPTUS AND MELALEUCA TREES rich in anti-infectious essential oils
Originally from the southwestern Pacific and Australia, eucalypts and their botanical cousins ??have very aromatic foliage from which essential oils are powerful bactericidal and widely used to treat respiratory infections (bronchitis), flu complicated with bronchitis
as well as urinary tract infections.
The European myrtle has very similar medicinal properties. voisines.
Copyright 2019 : Dr Jean-Michel Hurtel