NIS - libdoc.who.int - World Health Organization

Herba Origani
Heavy metals
For maximum limits and analysis of heavy metals, consult the WHO
guidelines on quality control methods for medicinal plant materials (33).
Radioactive residues
Where applicable, consult the WHO guidelines on quality control methods
for medicinal plant materials (33) for the analysis of radioactive isotopes.
Other purity tests
The content of mineral matter must not be more than 1% (1). Chemical,
sulfated ash, alcohol-soluble extractive and water-soluble extractive tests
to be established in accordance with national requirements.
Chemical assays
Herba Origani contains not less than 2.5% of volatile oil and a minimum
of 1.5% carvacrol and thymol in anhydrous drug. Volatile oil is quantitatively
determined by distillation, and the percentage content of phenols is
determined by gas chromatography (2). Whole Herba Origani contains
not less than 0.1% volatile oil. The cut drug contains not less than 0.08%
of volatile oil (1).
Major chemical constituents
Herba Origani contains 0.15–1.2% of volatile oil. The chief components
of the volatile oil are carvacrol (40–70%), γ−terpinene (8–10%), p-cymene
(2.80–10.00%), as well as α-pinene, myrcene, thymol, α-terpinene, estragole,
eugenol and (E)-β-ocimene, among others. There are also strains
that contain thymol, linalool with terpinen-4-ol, linalool, β-caryophyllene,
germacrene D and sabinene as the major components. The ethanol-water
extract contains flavonoids (naringin, luteolin-7-glucoside, diosmetin-7-
glucoside and apigenin-7-glucoside), rosmarinic acid (approximately 5%)
and other phenolic esters; tannins are also present (4, 7, 8, 17, 19, 24, 35–
38). The structures of the main characteristic constituents are presented
below.
CH 3
H 3
C
OH
H 3
C
OH
CH 3
carvacrol
CH 3
thymol
CH 3
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