Generally, pure essential oils can be subdivided into two distinct groups of chemical constituents; the hydrocarbons which are made up almost exclusively of terpenes (monoterpenes, sesquiterpenes, and diterpenes), and the oxygenated compounds which are mainly esters, aldehydes, ketones, alcohols, phenols, and oxides.
Terpenes - inhibit the accumulation of toxins and help discharge existing toxins from the liver and kidneys.
• Sesquiterpenes are antiseptic and anti-inflammatory.
Sesquiterpenes work as a liver and gland stimulant and contain caryophyllene and valencene. The research from the universities of Berlin and Vienna shows increased oxygenation around the pineal and pituitary glands.
Subsequent research has shown that sesquiterpenes have the ability to surpass the blood-brain barrier and enter the brain tissue. Other sesquiterpenes, like chamazulene and farnesol, are very high in anti-inflammatory and anti-bacterial activity. Chamazulene can be found in chamomile, tansy, and yarrow.
• Farnesene is anti-viral in action.
• Limonene has strong anti-viral properties and has been found in 90% of the citrus oils.
• Pinene has strong antiseptic properties and may be found in high proportions in the conifer oils such as pine, fir, spruce, and juniper.
• Other terpenes include camphene, cadinene, cedrene, dipentene, phellandrene, terpinene, sabinene, and myrcene.
Esters - are the compounds resulting from the reaction of an alcohol with an acid (known as etherification) Esters are common and are found in a large number of essential oils. They are also anti-fungal, calming and relaxing.
• Linalyl acetate may be found in bergamot, Clary sage, and lavender
• Geraniol acetate may be found in sweet marjoram.
• Other esters include bornyl acetate, eugenol acetate, and lavendulyl acetate.
Aldehydes - are highly reactive and characterized by the group C-H-O (Carbon, Hydrogen, Oxygen). Generally, they are anti-infectious with a sedative effect on the central nervous system.
They can be enough irritating when applied topically (citral being one example), but may have a profound calming effect when inhaled.
• Citral is very common with a distinctive antiseptic action. This also has an anti-viral application as with Melissa oil when applied topically on herpes simplex.
• Citronellal is also very common and has the same lemony scent as citral. Together with citral and neral, citronellas may be found in the oils of melissa, lemongrass, lemon, mandarin, lemon-scented eucalyptus, and citronella.
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