Folium Cynarae consists of the dried basal leaves of Cynara cardunculus
The correct name of the plant is Cynara cardunculus L. (Asteraceae) according to the currently accepted nomenclature.
Selected vernacular names
Alcachofa, alcachofra, alcaucil, alcaucoe, artichaut, artichaut commun, artichiocco, artichoke, artichoke thistle, Artischocke, artiskok, carcioffa, carciuffolo, cardo alcachofero,cardo senzaspine, cardoon, dofital ‘roza, edible thistle, enginar, garden artichoke, Gemüseartischocke, globe artichoke, hathi choka, hatichuk, kangar, kangar I dahri, kharshoul, kharsuf, kunjor, Scotch thistle, som-eonggeongqui.
A large herbaceous perennial, thorny plant, approximately 1.5 m in
The leaves are large, alternate, deeply dentate. The tall purple
flowers are grouped in large capitulums, 10–15 cm in diameter borne
by hardy ramified grooved stems, with sessile and almost entire leaves.
Leaves are very large, up to approximately 50 cm long by 25 cm wide with a long petiole approximately 1 cm thick; lamina deeply pinnatifid, forming flat, lanceolate segments with coarsely-toothed margins; upper surface brownish-green, lower surface greyish-white and densely covered with trichomes; segments with pinnate venation, the side veins terminating in a short point on each marginal tooth; midrib and petiole deeply grooved on the upper surface, the lower surface prominently raised, with several longitudinal ridges and covered with long, whitish trichomes.
Odour: faint, slightly sour; taste: salty at first, then bitter.
Lamina: The dorsiventral view reveals a fairly large and loosely packed palisade layer of cells.
Cells of the upper epidermis have straight to slightly sinuous anticlinal walls, whereas the cells of the lower epidermis are more wavy – walled.
Anomocytic stomata on both surfaces, more numerous on the lower surface, with covering trichomes scattered on the upper epidermis, especially over the veins, very abundant on the lower epidermis; individual trichomes mostly of the whiplash type with several small cells forming the uniseriate bases and very long, narrow and sinuous terminal cells intertwining to form a felted mass covering the surface; other less numerous, uniseriate covering trichomes composed of 4–6 cells, tapering to a blunt apex with the cells sometimes more or less globular to ovoid; fairly large glandular trichomes also abundant on both surfaces, with short, 1- or 2-celled stalk and a spherical head filled with a brownish secretion.
Midrib and petiole: Epidermal cells rectangular and longitudinally elongated, with scattered glandular and covering trichomes similar to those in the lamina.
Transverse section shows bands of collenchyma below both the upper and lower epidermises; a large vascular bundle in each ridge on the lower surface, and a number of smaller bundles arranged in an arc surrounding the groove on the upper surface; vascular bundles composed of a dense group of pericyclic fibres with thick, lignified walls, a wide area of thin-walled sieve tissue and a lignified xylem containing small vessels, tracheids and xylem parenchyma; below each xylem group a mass of lignified fibres, which, in the larger bundles, extends as a narrow layer on either side of the vascular tissue to join with the fibres of the pericycle; ground tissue composed of large-celled, rounded parenchyma, some with lignified walls.
Powdered plant material
Greyish-green to brown powder with faint odour; fragments of the lamina with more or less sinuous walls and anomocytic stomata; covering trichomes, scattered or in felted masses and large, glandular trichomes with brown contents; groups of lignified fibres and vessels from the midrib and petiole, the larger vessels with reticulate thickening.
General identity tests
Macroscopic and microscopic examinations, and thin-layer chromatography.
Tests for specific microorganisms and microbial contamination limits are as described in the WHO guidelines on assessing quality of herbal medicines with reference to contaminants and residues.
Foreign organic matter Not more than 2.0%.
Total ash Not more than 15.0%.
Acid-insoluble ash Not more than 4%.
Water-soluble extractive Not less than 25.0%.
Loss on drying Not more than 8%.
Uses supported by clinical data
Treatment of digestive complaints (e.g. dyspepsia, feeling of fullness, flatulence, nausea, stomach ache and vomiting). Adjunct treatment of mild to moderate hypercholesterolaemia.
Uses described in pharmacopoeias and well established documents
Orally for the treatment of atherosclerosis and kidney dysfunctions (diuretic)
One study has indicated that the crude drug may be of benefit for the treatment of irritable bowel syndrome , but further randomized controlled clinical trials are needed before any therapeutic recommendations can be made.
Uses described in traditional medicine
Oral treatment of anaemia, diabetes, fever, gout, rheumatism and urinary
Antiatherosclerotic and antihypercholesterolaemic activities
A dried aqueous extract of the leaves inhibited cholesterol biosynthesis from 14C-acetate in primary cultured rat hepatocytes in a concentration dependent biphasic manner with moderate inhibition (approximately 20%) being noted between 0.007 and 0.1 mg/ml and stronger inhibition at 1 mg/ml (80%).
Replacement of 14C-acetate by 14C-mevalonate largely prevented the inhibitory effects of the extracts, indicating inhibition of the activity of hydroxyl-methyl-glutaryl-CoA-reductase. Stimulation of hydroxyl- methyl-glutaryl-CoA-reductase activity by insulin was efficiently blocked by the extract.
Cynaroside and its aglycone luteolin, constituents of the extract, were mainly responsible for enzyme inhibition.
The effect of an extract of the leaves in vivo was investigated in four groups of
10 rats each fed an atherosclerogenic diet. Group one was administered 110 mg/kg body weight (bw) powdered leaves; group two, 80.0 mg/kg bw powdered Cynara cardunculus; group three, 10.0 mg/kg bw heparaxal; and group four served as the control.
Examination of tissue after 120 days showed that the leaf extract prevented formation of atherosclerotic changes, prevented serum cholesterol increase, caused a decrease in lipid phosphate, slightly increased the level of glycoproteins in the blood, prevented an increase in serum-globulin, decreased albumin, glycoproteins and liver cholesterol, and increased -globulin and globulin fractions.
Cynara cardunculus showed a similar but weaker activity.
A methanol extract of the leaves was shown to reduce serum triglyceride levels in olive oil-loaded mice.
Oral administration of the extract, at doses between 125 and 500.0 mg/kg bw, significantly suppressed serum triglyceride elevation 2 h after administration of olive oil. In contrast, 6 h after administration of olive oil, increases in triglyceride level were observed in the groups that received the extract at doses of 125.0 and 250.0 mg/kg bw. Orlistat, a lipase inhibitor, completely suppressed the serum triglyceride elevation at250.0 mg/kg bw.
Clofibrate, a hypolipidaemic medicine, also suppressed the triglyceride level at doses of 250.0 and 500.0 mg/kg bw.
Three sesquiterpenes(cynaropicrin, aguerin B and grosheimin) from the extract were isolated as the active components.
The effects of an aqueous extract of the leaves on taurolithocholate-induced
cholestatic bile canalicular membrane distortions were studied in primary cultured rat hepatocytes using electron microscopy.
Artichoke extracts at concentrations between 0.08 and 0.5 mg/ml were able to prevent the formation of canalicular membrane transformations in a dosedependent manner when added simultaneously with the bile acid.
However, prevention also occurred when the hepatocytes were preincubated
with the extracts, indicating that absorption of the bile acid to components
of the extracts was not involved.
The hepatoprotective activity of cynarin against carbon tetrachloride (CCl4) induced toxicity in isolated rat hepatocytes was compared with other phenolic compounds.
Only cynarin and, to a lesser extent, caffeic acid showed a cytoprotective effect. Treatment of rats with three consecutive doses of 500.0 mg/kg bw of an extract of the crude drug, administered by gavage 48, 24 and 1 h before CCl4 intoxication, produced a significant decrease in glutamic-oxaloacetic transaminase, glutamic-pyruvic transaminase (also known as alanine aminotransferase or ALT), direct bilirubin and glutathione levels, thus indicating a reduction in the potential for hepatotoxicity.
Primary cultures of rat hepatocytes exposed to tert-butyl hydroperoxide were used for characterizing the antioxidative and hepatoprotective potential of an aqueous extract of the crude drug and some selected constituents.
Addition of tert-butyl hydroperoxide to the culture media resulted in enhanced lipid peroxidation as measured by the production of malondialdehyde and enhanced cytotoxicity detected by leakage of lactate dehydrogenase.
The extract added prior to or simultaneously with tert-butyl hydroperoxide reduced both phenomena with a median effective concentration (EC50) of 95.0 and 12.0 μg leaf powder/ml, respectively.
Furthermore, the aqueous extract prevented the loss of intracellular glutathione
caused by tert-butyl hydroperoxide.
Several polyphenolic and flavonoid constituents of the extract were found to reduce malondialdehyde production.
The median effective concentration values were 8.1, 12.5, 15.2 and 28 μg/ml for caffeic acid, chlorogenic acid, cynarin and cynaroside, respectively.
Primary rat hepatocyte cultures exposed to tert-butyl hydroperoxide or cumene hydroperoxide were used to assess the antioxidative and protective potential of aqueous extracts of the leaves.
Both hydroperoxides stimulated the production of malondialdehyde, particularly when the cells were pretreated with diethylmaleate in order to diminish the level of cellular glutathione.
Addition of the extract did not affect basal malondialdehyde production, but prevented the hydroperoxide-induced increase of malondialdehyde formation in a concentration-dependent manner when presented simultaneously with or prior to the peroxides.
The effective concentrations were as low as 0.001 mg/ml.