Chemical Families

Chemical Families


This chemical family is the most prevalent in essential oils. These compounds are light (lower molecular weight) volatile and flow freely among the oil. These compounds comprise the front end (the first quarter) of most GC/MS analysis. For example, in most citrus oils limonene is a great indicator to quality this monoterpene makes up a majority of citrus plants and is a good indicator to the overall properties of the oil. A few good examples of oils with high limonene include: Lemon ,Ravensara , Elemi, and Lime


This type of chemical family has a larger molecular weight than the monoterpene family. These compounds are not as common in essential oils, but when present have exciting properties. Most of the synergistic healing pathways run through the sesquiterpene families. These compounds are less volatile and contribute less to the aroma of an oil. Caryophyllene is a sesquiterpene and is a great example of a constituent that has unique properties to help make well-balanced oil.


By adding an alcohol functional group to these terpene hydrocarbon chains, the chemical effects are drastically different when comparing to the previous chemical families. An alcohol added to a monoterpene chain is often called a monoterpenol, and when adding an -OH (alcohol) group to a sesquiterpene backbone the family is called a sesquiterpenol. These compounds now have an added oxidation pathway and can lead to more synergistic effects. Linalool is a very prevalent monoterpenol and is commonly known to help reduce stress.


Chemically a ketone is described as a double bonded oxygen atom that is usually isolated along a hydrocarbon chain (either monoterpene or sesquiterpene). These compounds are often linked to having some of the most oxidative effects and can lead to greater healing properties for essential oils that contain this family. Most ketones are very rare to find in plant material, but helichrysum is known to have some italidiones which are linked to regenerative effects.


In the essential oil field esters are very aromatic and help provide many of the soothing smells that we are all accustomed to experiencing when smelling many of the floral oils. Acetates specifically are what comprises most of the esters we find in plant materials. Along with being calming and soothing esters also have the ability to be anti-inflammatory in many cases.


This chemical family is not normally found in many essential oils, but when it is present it usually dominates the aroma profile. These compounds look a lot like ketones, but are bonded directly to a terminal hydrogen atom. These compounds are used to deter pests in some cases (citronellal) and are easily recognized by name as they have the -al suffix to denote their chemical composition.

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