Chemical Properties
Patchouli oil is produced by steam distillation of the dried leaves of Pogostemon cablin (Blanco) Benth. (Lamiaceae). It is a reddish-brown to greenish-brown, more or less viscous liquid with a characteristic, slightly camphoraceous, woody balsamic odor.
d2020 0.952–0.975; n20D 1.5050–1.5150; α20D ?60 ° to ?40 °; solubility: 1 vol in not more than 10 vol of 90% ethanol at 20 °C; acid number:max. 4; ester number:max. 10.
The patchouli shrub is cultivated primarily in Indonesia. It grows to 1m, but during harvesting, it is cut back to 10–15 cm. The oil yield from preferably sundried leaves is about 2%.
Although the sesquiterpene alcohol (?)-patchoulol is the main component of patchouli oil (27–35%), this compound contributes less to the characteristic odor of the oil than (+)-norpatchoulenol present only at a concentration of 0.35–1%. Other typical constituents are (+)-α-bulnesene (13–21%), (?)-α-guaiene (11–16%), (?)-β-patchoulene (1.8–3.5%), and (?)-seychellene(1–3%).
Chemical Properties
The oil is obtained by steam distillation of properly dried leaves in approximately 1.5 to 3.0% yields. The oil has a
typical camphoraceous odor and woody undernote imparted sometimes by adulteration of the oil with gurjum balsam. The classic
patchouly odor is recognizable in the high-quality oil manufactured in the Malaysian state of Johore and marketed under the name
of Paxamo Special Singapore.
Physical properties
Independent of its origin, the essential oil is a slightly viscous, brown liquid.
Definition
Extractives and their physically modified derivatives. Pogostemon cablin (Pogostemon patchouli), Labiatae.
Essential oil composition
The main known constituents include benzaldehyde, eugenol, cinnamaldehyde, patchouly alcohol (a tricyclic
alcohol, C15H260), two hydrocarbons (C15H24), and other minor unidentified components (Burdock, 1997).
Safety Profile
Low toxicity by ingestion and skin contact. A skin irritant. A combustible liquid. When heated to decompositionit emits acrid smoke and irritating vapors.