''Symphytum'' is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...
of flowering plants in the borage family,
Boraginaceae, known by the common name comfrey (pronounced ). There are 59 recognized species.
[WFO (2022): Symphytum L. Published on the Internet; http://www.worldfloraonline.org/taxon/wfo-4000037231. Accessed on: 14 Dec 2022] Some species and
hybrids, particularly ''
S. officinale'', ''
Symphytum grandiflorum'', and
''S.'' × ''uplandicum'', are used in
gardening
Gardening is the practice of growing and cultivating plants as part of horticulture. In gardens, ornamental plants are often grown for their flowers, foliage, or overall appearance; useful plants, such as root vegetables, leaf vegetables, fr ...
and
herbal medicine. They are not to be confused with ''
Andersonglossum virginianum'', known as wild comfrey, another member of the borage family.
Species
Species include:
*''
Symphytum asperum'' – prickly comfrey, rough comfrey
*''
Symphytum bulbosum'' – bulbous comfrey
*''
Symphytum brachycalyx'' - Palestine comfrey
*''
Symphytum caucasicum
''Symphytum caucasicum'', the beinwell, blue comfrey, or Caucasian comfrey, is an ornamental plant of genus '' Symphytum'' in the family Boraginaceae, which is native to the Caucasus
The Caucasus () or Caucasia (), is a region between the B ...
'' – Caucasian comfrey
*''
Symphytum grandiflorum'' – creeping comfrey
*''
Symphytum ibericum'' – Iberian comfrey
*''
Symphytum officinale
''Symphytum officinale'' is a perennial flowering plant in the family Boraginaceae. Along with thirty four other species of ''Symphytum'', it is known as comfrey. To differentiate it from other members of the genus ''Symphytum'', this species ...
'' – comfrey
*''
Symphytum orientale'' – white comfrey
*''
Symphytum tauricum'' – Crimean comfrey
*''
Symphytum tuberosum'' – tuberous comfrey
*''Symphytum'' × ''uplandicum'' (''S. asperum'' × ''S. officinale'', synonym: ''S. peregrinum'') – Russian comfrey, healing herb, blackwort, bruisewort, wallwort, gum plant
Cultivation
The Russian comfrey 'Bocking 14' cultivar was developed during the 1950s by
Lawrence D. Hills
Lawrence Donegan Hills (2 July 1911 – 20 September 1990) was a British horticulturalist and writer. In 1954, he founded the Henry Doubleday Research Association (HDRA; now Garden Organic) in Bocking, near Braintree, Essex. By the time he retir ...
, the founder of the
Henry Doubleday Research Association (the
organic gardening organization itself named after
Henry Doubleday, who first introduced Russian comfrey into Britain in the nineteenth century) following trials at
Bocking, Essex.
Propagation
Bocking 14 is sterile, and therefore will not set seed (one of its advantages over other cultivars as it will not spread out of control); thus, it is propagated from
root cuttings. The gardener can produce "offsets" from mature, strongly growing plants by driving a spade horizontally through the leaf clumps about below the soil surface. This removes the crown, which can then be split into pieces. The original plant will quickly recover, and each piece can be replanted with the growing points just below the soil surface, and will quickly grow into new plants. Offsets can also be purchased by mail order from specialist nurseries in order to initially build up a stock of plants.
Phytochemistry, folk medicine, and toxicity
Folk medicine
Traditional medicine (also known as indigenous medicine or folk medicine) comprises medical aspects of traditional knowledge that developed over generations within the folk beliefs of various societies, including indigenous peoples, before the ...
names for comfrey include knitbone, boneset, and the derivation of its Latin name ''Symphytum'' (from the Greek ''symphis'', meaning growing together of bones, and ''phyton'', a plant), referring to its ancient uses. Similarly, the common French name is ''consoude'', meaning to weld together. The tradition in different cultures and languages suggest a common belief in its usefulness for mending bones.
Comfrey contains mixed
phytochemical
Phytochemicals are chemical compounds produced by plants, generally to help them resist fungi, bacteria and plant virus infections, and also consumption by insects and other animals. The name comes . Some phytochemicals have been used as poison ...
s in varying amounts, including
allantoin,
mucilage,
saponins,
tannin
Tannins (or tannoids) are a class of astringent, polyphenolic biomolecules that bind to and precipitate proteins and various other organic compounds including amino acids and alkaloids.
The term ''tannin'' (from Anglo-Norman ''tanner ...
s,
pyrrolizidine alkaloid
Pyrrolizidine alkaloids (PAs), sometimes referred to as necine bases, are a group of naturally occurring alkaloids based on the structure of pyrrolizidine. Pyrrolizidine alkaloids are produced by plants as a defense mechanism against insect her ...
s, and
inulin, among others.
Pyrrolizidine alkaloids are responsible for comfreys production of hepatotoxicity.
Liver toxicity
Hepatotoxicity (from ''hepatic toxicity'') implies chemical-driven liver damage. Drug-induced liver injury is a cause of acute and chronic liver disease caused specifically by medications and the most common reason for a drug to be withdrawn fro ...
is associated with consuming this plant or its
extracts.
In modern
herbalism
Herbal medicine (also herbalism) is the study of pharmacognosy and the use of medicinal plants, which are a basis of traditional medicine. With worldwide research into pharmacology, some herbal medicines have been translated into modern remedie ...
, comfrey is most commonly used
topically.
In 2001, the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...
Food and Drug Administration
The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food ...
issued a ban of comfrey products marketed for internal use, and a warning label for those intended for external use. Comfrey is particularly contraindicated during pregnancy and lactation, in infants, and in people with liver, kidney, or
vascular diseases.
References
External links
*
Healthline
{{Taxonbar, from=Q161566
Boraginaceae genera
Taxa named by Carl Linnaeus