Volatile oil
n., plural: volatile oils
/ˈvɒlətaɪl ɔɪl/
Definition: Aromatic plant compounds with high vaporization rates
Table of Contents
Volatile Oil Definition
Volatile oils are aromatic compounds that are characterized by their volatility and inability to saponify. They are known for their distinctive fragrance and therapeutic remedies. They are of oily consistency and feel, especially those derived from plant tissues. Volatile oil is sometimes called an essential oil; the synonym essential oils refers particularly to the concentrated hydrophobic liquid with plant-derived, volatile aroma compounds.
The word “essential” refers to their essence because such oils contain what seems to be the essence of the plant’s characteristic fragrance. Ecologically, volatile oils help protect plants by deterring herbivores and pathogens. The oil also attracts pollinators. Because of their aromatic and biochemical properties, volatile oils have been used for centuries by humans for medicinal, cosmetic, and culinary purposes.
Here are the common features of volatile oils:
- They are volatile, meaning they can easily vaporize or evaporate readily at room temperature. Unlike fatty oils that do not evaporate when exposed to air and saponify, volatile oils evaporate into the air and thus, are capable of distillation.
- They emit strong, often pleasant odors.
- Volatile oils consist of terpenes, phenolics, and aliphatic molecules. The volatile oil components may vary significantly between different plant species and even within the same species.
Many essential oils are extracted from plants. Watch how:
Biology definition:
Volatile oil refers to plant-derived compounds with high vaporization rates. They are characterized by their volatility, aroma, and ecologically significant properties. Most volatile oils occur in leaves, flowers, stems, and seeds of plants.
Etymology: The term “volatile oil” originates from the Latin word “volatilis,” meaning “fleeting” or “evaporating,” and the English word “oil,” referring to the oily nature of these plant extracts.
Synonyms: essential oil; aromatic oil; plant oil; ethereal oils (archaic)
Variants: volatile essential oils; volatile plant oils
Types Of Volatile Oil Components
Volatile oils encompass a diverse array of organic compounds, with the most prevalent groups being terpenes, phenolics, and aliphatic molecules. These components collectively contribute to the unique fragrance and properties of each volatile oil.
Extraction Of Volatile Oils
Volatile oils may be produced naturally by extraction although they may also be made synthetically.
- Traditional extraction techniques: Extracting volatile oils from plant material involves two primary methods: steam distillation and solvent extraction. Steam distillation makes use of steam to gently coax the volatile oils from plant tissues. Alternatively, solvent extraction utilizes solvents to dissolve the oils, which are then separated from the plant material.
- Supercritical carbon dioxide extraction: This method utilizes supercritical carbon dioxide as a solvent to extract plant essential oils. This newer method is an advanced essential oil extraction process as it can preserve the oils’ quality and purity. Moreover, it offers a more sustainable and environmentally friendly alternative to traditional extraction techniques.
Human Uses Of Volatile Oils
Volatile oils are generally extracted for some of these uses:
- Medicinal and therapeutic applications: Volatile oils have been valued for centuries for their benefits in promoting the wellness of the human body. Their scents are used in aromatherapy and traditional medicine, such as for relaxation and stress relief, pain management, skin irritations, and skin care. Their high volatile oil contents make them incredibly potent, even in small quantities.
- Culinary and flavoring purposes: Volatile oils are used in culinary as seasoning blends. They enhance the flavors and aroma of dishes.
- Cosmetic And Perfumery Industry: The cosmetic and perfumery industry uses volatile oils for their scent. They are the essence of many fragrances in perfumes, lotions, and skincare products.
Ecological Functions
Role in plant-pollinator interactions
Volatile oils play a vital role in the survival and propagation of plants. One, in particular, is their ability to attract pollinators, like bees and butterflies with their scent. It, therefore, helps in enabling pollination.
Defense mechanisms against herbivores and pathogens
Plants utilize volatile oils as a natural defense mechanism. They help deter herbivores, discouraging them from feeding on the plant. They also protect plants from harmful microbes or pathogens as they may possess antimicrobial properties.
NOTE IT!
Volatile Oils: The Power of Aroma
Volatile oils are certainly essential oils, especially for plants. They are natural herbivore repellents. Animals that do not heed the volatile warning could end up regretting consuming the aromatic plants that turn out to contain aromatic compounds that can cause digestive discomfort.
Not only that!
The scent of these volatile oils could be taken as a “pleasant cue” by others. As these volatile oils are released during herbivory, they may be picked up by the natural enemies of those plant eaters.
As if by the plant’s summoning, the predators and parasitoids would come to its rescue as if an ally, preying or parasitizing on the plant’s herbivore.
As if hoisted as a “distress signal”, volatile oils together with the other volatile organic compounds (VOCs) may be picked up by neighboring plants, rousing them to prime their defenses, e.g., by intensifying their chemical arsenal or by recruiting natural predators or parasitoids, as plants’ collective resistance to herbivory.
References
- Oils, Volatile – MeSH – NCBI. (2023). Nih.gov. https://www.ncbi.nlm.nih.gov/mesh?Db=mesh&Cmd=DetailsSearch&Term=%22Oils,+Volatile%22%5BMeSH+Terms%5D#:~:text=Oils%20which%20evaporate%20readily.,(the%20more%20solid%20constituent).
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