FAMILY: Lauraceae
SYNONYMS: Madagascar clove-nutmeg, aromatic ravensare, Ravensara anisata, Agatophyllum aromaticum.
GENERAL DESCRIPTION: The genus Ravensara includes many species of evergreen trees or shrubs native to Madagascar and the Comoro Islands. These evergreen trees can grow up to 30 metres tall in rainforests, usually on all type of soils. The best-known species of this genus is R. aromatica used for its essential oil. It grows to a height of about 20 metres with several buttress roots at the base, with reddish bark, dark green shiny leaves and small yellow-green flowers. The fruit, a fleshy berry, are an important food source for birds. All parts of the tree are aromatic.
DISTRIBUTION: R. aromatica is native to Madagascar and once thrived in the rainforests, but is now an endangered species due to de-forestation and over-exploitation. By the early part of this century, this species required protection as the production of the essential oil from the bark, used by the pharmaceutical industry, was particularly destructive as it required felling the trees. Only the leaves can now be used for oil production, to prevent cutting down the whole tree. There is now a conservation programme in place to protect these trees: it is therefore important to obtain the essential oil of the leaf from sustainable sources.
OTHER SPECIES: There are over 30 species of Ravensara that grow in Madagascar. The common name of the genus Ravensara is actually a latinization of the Malagasy term ravintsara which means ‘good leaves’, a term originally used by the natives to describe another species of tree. European botanists in the nineteenth century made several attempts to classify the various indigenous aromatic trees of Madagascar, but due to the similarity of the two names ‘ravintsara’ and ‘ravensara’ they came to be used almost interchangeably. The botanical confusion between these two species has continued to cause a great deal of uncertainty as to their precise origins. In fact, the essential oils derived from these two species are very different aromatically as well as in their chemical composition. However, most of so-called ‘ravensara’ oil from Madagascar, is actually produced from the Cinnamomum camphora species (even if it is said to derive from R. aromatica) so great care needs to be taken in identifying the correct source of each oil. See also entry for Ravintsara.
HERBAL/FOLK TRADITION: In Madagascar, this genus of trees is commonly called hazomanitra, meaning ‘tree that smells’, as the whole part of the plant is aromatic. Traditionally, the Malagasy people used the bark and stem as a tonic and as an antibacterial medicine. The leaves were also burnt in homes after a death to prevent the spread of disease while the anise-flavoured bark was used in the production of local rum. The oil from the Ravensara genus is referred to locally as ‘the oil that heals’ because it is used for so many different conditions. The essential oil from the bark, R. anisata (a synonym for R. aromatica) is known as ‘havozo’ and has a strong anise-like odour.
ACTIONS: Antiviral, antibacterial, antifungal, anti-infectious, antiseptic, antispasmodic, expectorant, immune-stimulant.
EXTRACTION: 1. Ravensara oil is steam distilled from the leaves of the plant. 2. The essential oil distilled from the bark is called havozo. 3. An essential oil is also extracted occasionally from the fleshy fruits or berries.
CHARACTERISTICS: 1. Ravensara oil (from the leaf) has a sweet, fresh, slightly lemony, licorice-like scent with an earthy undertone. 2. Havozo (from the bark) has a fresh, strong aniseed-like odour.
PRINCIPAL CONSTITUENTS: 1. The oil from the leaf contains relatively small amounts of methyl chavicol (estragole), myrcene, a-pinene and linalool with the main constituents being limonene (approx. 13–22 per cent) and sabinene (approx. 10–16 per cent) with very little 1,8-cineole (1.8–3.3 per cent). 2. Havozo (bark oil) has a high methyl chavicol content (up to 90 per cent).
SAFETY DATA: 1. Ravensara (R. aromatica) is generally considered a safe oil (non-toxic and non-irritant) although it is best avoided during pregnancy. 2. Havozo oil is not recommended for use in aromatherapy due to its high methyl chavicol content, as it is a suspected carcinogen. Research has shown, nevertheless this oil has potent anti-microbial properties, being active against E. coli.
AROMATHERAPY/HOME: USE
Skin care: Chickenpox, cold sores, herpes (all types), shingles.
Circulation muscles and joints: Aching limbs, arthritis, cramp, gout, muscle fatigue, rheumatism.
Respiratory system: Bronchitis, colds, congestion, influenza, sinusitis, throat and lung infections, whooping cough.
Immune system: Viral infections especially herpes, hepatitis, chicken pox.
Nervous system: Anxiety, insomnia, nervous tension, stress.
OTHER USES: Ravensara species have been used for a long time to produce essential oils for the pharmaceuticals industry. In perfumery usage, it is employed as a middle note.