Hypericum perforatum, St. John’s Wort, produces two products used in aromatherapy, a macerated oil and an essential oil.
St. John’s Wort is a perennial herb native to Europe, North Africa and western Asia, that was then introduced and naturalized in parts of Africa, Asia, Australia and the Americas. It has small, stalkless leaves that are covered with tiny perforations, which are in fact translucent glands. It also has an extensive, creeping rhizome. It flowers in summer and its bright yellow flowers have black dots.
St. John’s Wort has a long tradition of being associated with healing wounds and inflammations. It was called the “Grace of God’. In England it was said it cured mania; in Russia it was used for protection and in Brazil it was known as an antidote to snakebite. When the leaves are crushed they release a balsamic odor similar to incense, and it was believe that this was strong enough to drive away evil spirits. The plant is also associated with St. John, but there are a couple of different versions of this association. One says that it was called St. John’s Wort because the red pigment of the crushed flowers signified the blood of St. John at his beheading, and the herb is in full flower on June 24th St. John’s Day. The other says that the name came from the Knights of St. John of Jerusalem, who used it to heal wounds during the Crusades. The herb has been used extensively in for form of a tea, liquid extract, tincture and macerated oil.
Although they are both produced from the same plant, and while there are conditions that can be treated by both the macerated oil and the essential oil, there are also differences between the two, particularly as the methods used to produce them will affect the chemistry of the final product.
The red macerated oil is produced by steeping the hypericum buds and flowers in a good quality vegetable oil (virgin olive oil is usually the preferred oil) for many days in full sun, with occasional agitation. After which the plant material is filtered off. It is said that the exposure to sunlight results in a four-fold increase in the flavonoid content. Smith et al (1996) recommended that the flowers be macerated in oil at 45 degrees Centigrade, while Hobbs (1989) recommends macerating at 70 degrees Centigrade for 12 – 24 hours.
A yellow essential oil is obtained through steam distillation of the flowering tops with a yield of 3.5% or less and contains Monoterpenes (42 – 45%); Sesquiterpenes (3 – 5%); Alkanes (41%); Alcohols (0.2 – 2.5%).
Both the macerated oil and the essential oil would be used topically.
The macerated oil is recommended as being beneficial for wounds where there is nerve tissue damage; inflamed nerve conditions like neuralgia, sciatica and fibrositis; on burns and inflammations, including sunburn. Len Price says that the oil will lower the skin temperature; he also suggests that the oil can be massaged on the lower back in cases of bed wetting; and use it for haemorrhoids, gout, rheumatism, sores, ulcers and wounds. Said to be an excellent oil for use on the skin as it is soothing, antiseptic and analgesic. It may also be a cosmetic skin tightener.
Cautions: no known contraindications to the judicious use of the macerated oil.
The essential oil has been used traditionally in skin care for eczema, inflamed, irritated or traumatized skin; fungal infections. It has also been used for muscular aches and pains, back injuries and spinal trauma as well as nerve pain. It may also be helpful for dyspepsia. I have also heard that it is excellent for preventing jet lag. On a psychological level it can be considered for nervous tension, depression, stress and insomnia. It is also suggested that it may be helpful in dealing with addictions and when there has been deep emotional wounding.
Cautions: Not a lot of information is available however it is generally considered safe to use. Do keep in mind that skin sensitization could occur if the oil has become oxidized.
One of the active ingredients occurring in the plant is hypericin which can be powerfully photoactive when ingested. On the other hand, hypericin is not present in the essential oil as this large molecule does not make it across the steam distillation process. (Tisserand and Young)