Definition
Spathulenol is a naturally occurring sesquiterpene alcohol with the molecular formula C₁₅H₂₆O. It is found as a constituent of the essential oils of various aromatic plants and is noted for its characteristic odor and potential biological activities.
Overview
Spathulenol belongs to the class of sesquiterpenes, which are terpenoid compounds built from three isoprene units (C₅). It is typically isolated from essential oils extracted from plants such as oregano (Origanum vulgare), thyme (Thymus spp.), marjoram (Origanum majorana), and several species of the genus Spathularia. The compound contributes to the aroma profile of these oils and has been investigated for antioxidant, anti‑inflammatory, and antimicrobial properties in vitro. Commercially, spathulenol is not produced in bulk but is encountered as a minor to moderate component (often ranging from 0.1 % to a few percent) of essential oil mixtures used in flavoring, fragrance, and aromatherapy applications.
Etymology/Origin
The name “spathulenol” derives from the earlier identified hydrocarbon “spathulen,” itself named after the fungus genus Spathularia, from which the hydrocarbon was first isolated. The suffix “‑ol” denotes the presence of a hydroxyl (‑OH) functional group, indicating that the compound is the alcohol derivative of spathulen.
Characteristics
| Property | Details |
|---|---|
| Chemical formula | C₁₅H₂₆O |
| Molecular weight | 222.37 g mol⁻¹ |
| Structure | A bicyclic sesquiterpene skeleton bearing a single secondary alcohol group. The exact stereochemistry is reported as (3aR,7aS)‑, but variations exist depending on the plant source. |
| Physical state | Colorless to pale‑yellow liquid at ambient temperature. |
| Solubility | Practically insoluble in water; soluble in organic solvents such as ethanol, ether, and chloroform. |
| Odor | Herbal, woody, and slightly spicy aroma, contributing to the sensory profile of many essential oils. |
| Natural occurrence | Detected in essential oils from Origanum spp., Thymus spp., Spathularia fungi, Cistus spp., and some Eucalyptus species. |
| Biological activities | In vitro studies have reported antioxidant capacity (e.g., DPPH radical scavenging), modest anti‑inflammatory effects (inhibition of nitric oxide production in macrophages), and antimicrobial activity against certain Gram‑positive bacteria. These findings are preliminary and have not been fully validated in clinical settings. |
| Safety | Generally regarded as safe (GRAS) when present in essential oil preparations at typical usage levels. No specific toxicological data are available for isolated spathulenol; occupational exposure limits have not been established. |
Related Topics
- Sesquiterpenes – A diverse group of C₁₅ terpenoids that include compounds such as farnesol, humulene, and β‑caryophyllene.
- Essential oils – Volatile aromatic extracts from plants in which spathulenol may appear as a minor constituent.
- Terpenoid biosynthesis – The enzymatic pathway (mevalonate or methylerythritol phosphate routes) that produces sesquiterpene backbones, including spathulenol.
- Phytochemistry – The study of chemicals derived from plants, encompassing the identification and functional assessment of compounds like spathulenol.
- Aroma compounds – Volatile substances responsible for scent and flavor, of which spathulenol is a representative sesquiterpene alcohol.
Note: The information presented reflects the current state of peer‑reviewed literature and authoritative chemical databases. Where data are limited, especially regarding detailed toxicology and clinical efficacy, the statements are accordingly qualified.