Milk thistle | |
---|---|
Silybum marianum | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Asterales |
Family: | Asteraceae |
Subfamily: | Carduoideae |
Tribe: | Cardueae |
Subtribe: | Carduinae |
Genus: | Silybum Adans. |
Type species | |
Carduus marianus [1] | |
Species | |
Synonyms [2] | |
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Silybum (milk thistle) is a genus of two species of thistles in the family Asteraceae. [1] [3] The plants are native to the Mediterranean regions of Europe, [4] North Africa, and the Middle East. One species has been introduced elsewhere, including in North America. [5] The name "milk thistle" derives from a feature of the leaves, which are prominently banded with splashes of white. Historically, these milky bands were said to be Mother Mary's milk, and this is the origin of another common name, St. Mary's thistle. The most widespread species is Silybum marianum . [6]
Claims have been made since ancient times[ when? ][ where? ] that the active flavanoid-lignan (flavanolignan) group of constituents, called silymarin, contained only in the seed shell has liver-protective and regenerative properties, as well as antioxidant effects. Chemical, pharmacological, and safety research started in Germany in the 1950s[ citation needed ].
Members of this genus grow as annual or biennial plants. The erect stem is tall, branched and furrowed but not spiny. The large, alternate leaves are waxy-lobed, toothed and thorny, as in other genera of thistle. The lower leaves are sessile (attached to the stem without petiole). The upper leaves have a clasping base. They have large, disc-shaped pink-to-purple, rarely white, solitary flower heads at the end of the stem. The flowers consist of tubular florets. The phyllaries under the flowers occur in many rows, with the outer row with spine-tipped lobes and apical spines. The fruit is a black achene with a white pappus. [7]
The two species hybridise naturally, the hybrid being known as Silybum × gonzaloi Cantó, Sánchez Mata & Rivas Mart. (S. eburneum var. hispanicum x S. marianum)
Silybum marianum is by far the more widely known species. Milk thistle is believed to give some remedy for liver diseases (e.g. viral hepatitis) and the extract, silymarin, is used in medicine. Mild gastrointestinal distress is the most common adverse event reported for milk thistle. The incidence is the same as for placebo. [10] A laxative effect for milk thistle has also been reported infrequently. [11]
For many centuries extracts of milk thistle have been recognized as "liver tonics." [12] Milk thistle has been reported to have protective effects on the liver and to greatly improve its function. It is typically used to treat liver cirrhosis, chronic hepatitis (liver inflammation), toxin-induced liver damage including the prevention of severe liver damage from Amanita phalloides ('death cap' mushroom poisoning), and gallbladder disorders. [11] [13]
Reviews of the literature covering clinical studies of silymarin vary in their conclusions.
The name destroying angel applies to several similar, closely related species of deadly all-white mushrooms in the genus Amanita. They are Amanita bisporigera and A. ocreata in eastern and western North America, respectively, and A. virosa in Europe. Another European species of Amanita referred to as the destroying angel, Amanita verna - also referred to as the 'Fool's mushroom' - was first described in France in 1780.
Bellis is a genus of flowering plants in the family Asteraceae.
Variegation is the appearance of differently coloured zones in the leaves and sometimes the stems and fruit of plants. Species with variegated individuals are sometimes found in the understory of tropical rainforests, and this habitat is the source of a number of variegated houseplants. Variegation is caused by mutations that affect chlorophyll production or by viruses, such as mosaic viruses, which have been studied by scientists. The striking look of variegated plants is desired by many gardeners, and some have deliberately tried to induce it for aesthetic purposes. There are a number of gardening books about variegated plants, and some gardening societies specialize in them.
Petasites hybridus, also known as the butterbur, is a herbaceous perennial flowering plant in the family Asteraceae that is native to Europe and northern Asia.
Antennaria is a genus of dioecious perennial herbs in the family Asteraceae, native to temperate regions of the Northern Hemisphere, with a few species in temperate southern South America; the highest species diversity is in North America. Common names include catsfoot or cat's-foot, pussytoes and everlasting.
Onopordum, or cottonthistle, is a genus of plants in the tribe Cardueae within the family Asteraceae. They are native to southern Europe, northern Africa, the Canary Islands, the Caucasus, and southwest and central Asia. They grow on disturbed land, roadsides, arable land and pastures.
Sonchus is a genus of flowering plants in the tribe Cichorieae within the family Asteraceae and are commonly known as sow thistles. Sowthistles are annual, biennial or perennial herbs, with or without rhizomes and a few are even woody.
Silibinin (INN), also known as silybin (both from Silybum, the generic name of the plant from which it is extracted), is the major active constituent of silymarin, a standardized extract of the milk thistle, containing a mixture of flavonolignans consisting of silibinin, isosilibinin, silychristin, silidianin, and others. Silibinin itself is a mixture of two diastereomers, silybin A and silybin B, in approximately equimolar ratio. The mixture exhibits a number of pharmacological effects, particularly in the fatty liver, non-alcoholic fatty liver, non-alcoholic steatohepatitis, and there is great clinical evidence for the use of silibinin as a supportive element in alcoholic and Child–Pugh grade 'A' liver cirrhosis. However, despite its several beneficial effects on the liver, silibinin and all the other compounds found in silymarin, especially silychristin seem to act as potent disruptors of the thyroid system by blocking the MCT8 transporter. The long term intake of silymarin can lead to some form of thyroid disease and if taken during pregnancy, silymarin can cause the development of the Allan–Herndon–Dudley syndrome. Although this information is not being taken into consideration by all regulatory bodies, several studies now consider silymarin and especially silychristin to be important inhibitors of the MCT8 transporter and a potential disruptor of the thyroid hormone functions.
Agropyron is a genus of Eurasian plants in the grass family), native to Europe and Asia but widely naturalized in North America.
Cirsium arvense is a perennial species of flowering plant in the family Asteraceae, native throughout Europe and western Asia, northern Africa and widely introduced elsewhere. The standard English name in its native area is creeping thistle. It is also commonly known as Canada thistle and field thistle.
Thistle is the common name of a group of flowering plants characterised by leaves with sharp prickles on the margins, mostly in the family Asteraceae. Prickles can also occur all over the plant – on the stem and on the flat parts of the leaves. These prickles are an adaptation that protects the plant from being eaten by herbivores. Typically, an involucre with a clasping shape similar to a cup or urn subtends each of a thistle's flower heads. The typically feathery pappus of a ripe thistle flower is known as thistle-down.
Silybum marianum is a species of thistle. It has various common names including milk thistle, blessed milkthistle, Marian thistle, Mary thistle, Saint Mary's thistle, Mediterranean milk thistle, variegated thistle and Scotch thistle. This species is an annual or biennial plant of the family Asteraceae. This fairly typical thistle has red to purple flowers and shiny pale green leaves with white veins. Originally a native of Southern Europe through to Asia, it is now found throughout the world.
Cnicus benedictus, known by the common names St. Benedict's thistle, blessed thistle, holy thistle and spotted thistle, is a thistle-like plant in the family Asteraceae, native to the Mediterranean region, from Portugal north to southern France and east to Iran. It is known in other parts of the world, including parts of North America, as an introduced species and often a noxious weed. It is the sole species in the monotypic genus Cnicus. Other species once included in the genus have largely been reclassified to Cirsium, Carduus, and Centaurea.
Chronic liver disease in the clinical context is a disease process of the liver that involves a process of progressive destruction and regeneration of the liver parenchyma leading to fibrosis and cirrhosis. "Chronic liver disease" refers to disease of the liver which lasts over a period of six months. It consists of a wide range of liver pathologies which include inflammation, liver cirrhosis, and hepatocellular carcinoma. The entire spectrum need not be experienced.
Antennaria dioica is a Eurasian and North American species of flowering plant in the family Asteraceae. It is a perennial herb found in cool northern and mountainous regions of Europe and northern Asia (Russia, Mongolia, Japan, Kazakhstan, China, and also in North America in Alaska only.
Lactuca serriola, also called prickly lettuce, milk thistle, compass plant, and scarole, is an annual or biennial plant in the tribe Cichorieae within the family Asteraceae. It has a slightly fetid odor and is commonly considered a weed of orchards, roadsides and field crops. It is the closest wild relative of cultivated lettuce.
Talinum paniculatum is a succulent subshrub in the family Talinaceae that is native to much of North and South America, and the Caribbean countries. It is commonly known as fameflower, Jewels-of-Opar, or pink baby's-breath.
Flavonolignans are natural phenols composed of a part flavonoid and a part phenylpropane.
Echinops echinatus, the Indian globe thistle, commonly known as Usnakantaka, is a species of globe thistle, found in India, Pakistan, and Sri Lanka. Indian globe thistle is an erect branched herb about 100 cm high. It has short, stout stems, branching from the base, covered with white cottony hair. Alternately arranged oblong, deeply pinnatifid leaves are 7–12 cm long. Flower heads occur in solitary white spherical balls, 3–5 cm across. Petals of the tiny white disc florets are 5 mm long. Flowers are surrounded by straight, strong, white bristles. Often misidentified with Silybum marianum (L.) Gaertner, it is colloquially known as Camel's thistle.
Lactuca floridana, commonly known as woodland lettuce, Florida lettuce, or false lettuce is a North American species of wild lettuce. It is native across much of central Canada and the eastern and central United States.
Media related to Silybum at Wikimedia Commons