The Eucalyptus Genus
The Eucalyptus genus belongs to the Myrtaceae botanical family, along with many other important aromatic plants which produce essential oils, such as the Melaleuca genus which includes tea tree oil as well as Myrtus, which includes myrtle oil. There are over 700 species of eucalyptus of which at least 500 produce a type of essential oil, so it is a very large genus. Because of their potential medicinal value, ongoing research is being carried out into the different constituents of each oil, which can roughly be divided into three categories: the camphoraceous oils, such as the Blue Gum (Eucalyptus globulus var globulus) and the Blue-leaved Mallee (E. polybractea) containing large amounts of 1,8-cineole; the mint – scented species such as the Peppermint Eucalyptus (E. piperita) containing mainly piperitone; and the citrus-scented varieties such as the Lemon-Scented Eucalyptus (E. citriodora) containing mainly citronellal.
Most Eucalyptus species are native to Australia and have featured as important local remedies for thousands of years, second only to the tea tree plant (Melaleuca Alternifolia). The indigenous peoples of Australasia have traditionally used the leaves of the eucalyptus tree to treat respiratory conditions such as coughs, joint pain and infected skin conditions, as well as for fever. Later it was commonly known as ‘fever tree’ by the Europeans because of its potent medicinal properties. At Aqua Oleum we offer 3 types of eucalyptus oil: Blue Gum (Eucalyptus globulus) – a 100% pure oil as well as in an organically produced oil – plus the Lemon-Scented Eucalyptus oil (E.citriodora), as the latter has different but equally valuable therapeutic properties.
The Blue Gum (Eucalyptus Globulus)
The Blue Gum Eucalyptus is a beautiful evergreen tree up to 15 metres high with long narrow leaves, creamy-white flowers and a smooth, pale grey bark. The essential oil is produced by steam distillation of the leaves and twigs and is a mobile almost colourless liquid with a pungent fresh, slightly woody-sweet camphoraceous odour. It is the 1,8-cineole, a remarkable chemical constituent that has been well researched, that is responsible for the benefits to respiratory health. This is the most commonly available type of essential oil produced from the Eucalyptus genus having pronounced stimulating, anti-microbial, analgesic, antiseptic, anti-inflammatory, anti-bacterial, antispasmodic, antioxidant, antiviral, hypotensive, mucolytic, expectorant
and decongestant properties.
By simply adding a few drops of eucalyptus oil to a diffuser at home, it will instantly help to purify the room of any airborne germs and infections, such as from colds or flu. Research has confirmed its natural mucolytic properties which help to thin excess mucus, giving the respiratory system a major boost by soothing congested coughs and bronchitis and in some cases, asthma. The oil can be included in chest rubs for congested coughs, but because the oil can cause skin sensitisation and skin irritation in some individuals, it is important to only use it in low dilutions topically. Since eucalyptus oil has pronounced anti-microbial, anti-bacterial and antiviral properties, it acts as a good general preventive aid during epidemics or outbreaks of flu, especially during the winter months. It has been found to protect against a wide variety of bacterial infections and research has shown it to be particularly effective against E. coli and Candida albicans.
A 2008 study published in BMC Immunology, showed that Blue Gum Eucalyptus is also able to stimulate an immunity phagocytic response – the process whereby the immune system consumes and destroys foreign particles and dangerous pathogens. The analgesic and anti-inflammatory properties of Blue Gum Eucalyptus oil it makes an excellent massage treatment for sore, arthritic joints and sports injuries. In contemporary Western and Eastern medicine, it is commonly used in treatments to relieve joint disorders, muscular aches and pains, strains, poor circulation and for treating osteoarthritis. For this purpose, the oil can be topically applied in a 3% dilution (using a carrier oil such as sweet almond oil) and massaged gently into the affected area for rapid relief. Note: Blue Gum Eucalyptus oil it not suitable for young children of under 3, during pregnancy and should never be taken internally!
The Lemon-Scented Eucalyptus (E. Citriodora)
The Lemon-Scented Eucalyptus (E. Citriodora) is fast-growing, attractive tall evergreen tree with a smooth, dimpled bark, blotched in grey, cream and pink, much cultivated as an ornamental plant. The young leaves are oval, while mature leaves are narrow and tapering. A pale, mobile essential oil is steam distilled from the leaves and twigs having a strong, fresh lemony scent. Like the Blue Gum oil, this oil has powerful invigorating, stimulating, antiseptic, antiviral and bactericidal properties. Aboriginal populations in Australia have traditionally applied the aromatic leaves from lemon eucalyptus to wounds or cuts as an anti-septic salve to prevent any infection developing: recent tests have confirmed its outstanding fungicidal, anti-septic and bactericidal properties. As such, it can be used to treat a range of skin infections, once diluted to 3% in the form of an ointment, such as for treating athlete’s foot, shingles, ulcers, abscesses or infected nail beds. According to scientific research, lemon-scented eucalyptus, may chang and lemongrass, which all contain high amounts of citronellal, also exhibit excellent anti-microbial activity which may be especially effective in fighting airborne viral infections.
Nevertheless, the most common use of lemon-scented eucalyptus essential oil is for repelling insects due its high content of citronellal which can be effective for up to 8 hours after application. In fact, lemon eucalyptus essential oil has been proven to be a viable replacement for DEET, being just as effective. However, the oil can cause sensitisation in some individuals, so it is important to use in dilution only and always do a patch test first before topical application. Note: it not suitable for young children and should never be taken internally!