NIS - libdoc.who.int - World Health Organization

WHO monographs on medicinal plants commonly used in the Newly Independent States (NIS)
tive dose of 16.2 mg/ml. The median effective dose for the antioxidant
activity of the ethanol-aqueous extract was estimated to be 16 mg/ml as
assessed by a colorimetric assay (63, 64). In addition, the antioxidant activity
of the diethyl ether extract of dried leaves of Origanum vulgare
(concentration 0.02%) was demonstrated when assayed against corn oil,
soybean oil and olive oil (65). The water-soluble active ingredients were
isolated, and their structures were determined. Over 70% radical scavenging
activity was found for two of them – rosmarinic acid and 4´-O−βd-glucopyranosyl-3´,4´-dihydroxybenzyl
protocatechuate – when applied
at 2 × 10 -5 M in the 1,1-diphenyl-2-picrylhydrazyl test (66).
Antihyperglycaemic activity
An aqueous extract of dried leaves of Origanum vulgare exhibited antihyperglycaemic
activity in vivo when administered to rats by the intragastric
route at a dose of 20 mg/kg body weight (bw) (46). Commercial
samples of Origanum leaf (concentration 12.5 mg/ml) exhibited insulin
potentiating effects in vitro (67).
Antimutagenic activity
The aqueous and methanol extracts of dried and fresh leaves of Origanum
vulgare exhibited desmutagenic activity in an in vitro model, at a concentration
of 10 µg/agar plate of Salmonella typhimurium TA98, against
3-amino-1-methyl-5H-pyrido[4,3-b]indole-induced mutagenesis (68).
Both the essential oil and carvacrol were shown to strongly inhibit mutagenicity
induced by 4-nitro-o-phenylenediamine and 2-aminofluorene in
the presence or absence of a metabolic activator, which would suggest a
protective effect against cancer (69).
Toxicology
In mice, the median lethal dose for an aqueous-ethanol extract (1:1) of the
entire plant has been recorded as > 1 g/kg (by intraperitoneal injection)
(70). The essential oil of the aerial parts of the plant, at a concentration of
0.01%, inhibited proliferation of rabbit epidermal CA-HEP-2 cells, Vero
cells, and cultured HeLa cells (71).
Clinical pharmacology
No information was found.
Adverse reactions
No information was found.
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