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Black Bryony - Tamus communis L.This is a common European twining vine with tuberous roots and cordate leaves and red berries [syn: black bryony, black
bindweed, Tamus communis].
The whole plant is poisonous due to
its saponin content. Although toxic, saponins are very poorly absorbed
by the body and so tend to pass through without causing harm. They are
also broken down by thorough cooking. Saponins are found in many plants,
including several that are often used for food, such as certain beans. It
is advisable not to eat large quantities of food that contain saponins.
Saponins are much more toxic to some creatures, such as fish, and hunting
tribes have traditionally put large quantities of them in streams, lakes
etc in order to stupefy or kill the fish. The toxic effect of this
plant is not caused by saponins, but by calcium oxalate crystals which are
found mainly in the fruit. Black Bryony belongs to a family of twining and climbing plants which
generally spring from large tubers, some of which are cultivated for food,
as the Yam, which forms an important article of food in many tropical
countries. Great Britain only furnishes one species of this tribe,
Tamus communis, which, from its powerful, acrid and cathartic
qualities, ranks as a dangerous irritant poison. It is a very common plant in woods and hedges, with weak stems twining
round anything within reach, and thus ascending or creeping among the
trees and bushes to a considerable distance. The plant has been confused with the white bryony -
Bryonia cretica
L. ssp dioica Tutin (syn. Bryonia dioica Jacq.) in
the family Cucurbitaceae, from which it may be distinguished readily by
its lack of tendrils. Description Perennial Climber growing to 3.5 m. at a medium rate. It is hardy to
zone 5.
The plant prefers light (sandy), medium (loamy) and heavy (clay) soils,
requires well-drained soil and can grow in heavy clay soil. The plant
prefers acid, neutral and basic (alkaline) soils. It can grow in
semi-shade (light woodland) or no shade. It requires moist soil. The plant
can tolerates strong winds but not maritime exposure. The large, fleshy root is nearly cylindrical, 1 to 1 1/2 inch in
diameter, 3 to 4 inches long or more, black on the outside and exceedingly acrid.
Although an old cathartic medicine, is a most dangerous remedy when
taken internally. It is like that of the yam, thick and tuberous and
abounding in starch, but too acrid to be used as food in any manner.
The young shoots are said to be good eating when dressed like
Asparagus- the Moors eat them boiled with oil and salt, after they have
been first soaked in hot water. The generic name Tamus is given to the plant from the belief
that it is the same as that referred to in the works of
Pliny under the
name of Uva Taminia. The Greeks use the young suckers like Asparagus, which they much
resemble, as also do Istrians. A variation, T. cretica is a native of Greece and the Greek Archipelago.
Requires a moist well-drained fertile soil[17]. A climbing plant, the weak stems support themselves by twining around
other plants and are capable of growing quite high up into shrubs and
trees[4]. Dioecious. Male and female plants must be grown if seed is required.
Seed - sow in a cold frame in early spring or as soon as the seed is
ripe in the autumn. Prick out the seedlings into individual pots once they
are large enough to handle, and plant out in the summer or in late spring
of the following year. Edible Uses Medicinal Action and Uses
A tincture made from the root proves a most useful application
to unbroken chilblains, and also the fruits, steeped in gin, are
used for the same remedy. Black Bryony is a popular remedy for removing discoloration caused by
bruises and black eyes, etc. The fresh root is scraped to a pulp and
applied in the form of a poultice.
Histamin: The plant is rich in saponins so must be used with caution. It has a
very powerful cathartic affect and ranks as a dangerous irritant poison.
It is not normally used internally, but the macerated root is applied
externally as a poultice to bruises, rheumatic joints etc. This should not
be done without expert advice since it can cause painful blisters. The
root is used fresh or can be harvested in the autumn and dried for later
use. The expressed juice of the fresh root, mixed with a little white wine,
has been used as a remedy for gravel, being a powerful diuretic, but it is
not given internally now, and is not included in the British
Pharmacopoeia. Death in most painful form is the result of an overdose,
while the effect of a small quantity, varying not with the age only, but
according to the idiosyncrasies of the patient, leaves little room for
determining the limit between safety and destruction. The expressed juice
of the root, with honey, has also been used as a remedy for asthmatic
complaints, but other remedies that are safer should be preferred. Both the rubefacient slime from the rhizome and the juice from the
berry contain calcium oxalate raphides - measuring an average 450 μm in
length and 11 μm in diameter in the berry juice, and an average 250 μm in
length and 8 μm in diameter in the slime from the rhizome - which are
sharply pointed at both ends. They are responsible for mechanical
irritation when rubbed into the skin. In addition, the rhizome contains
histamine and saponins, both of which may contribute to the observed skin
response following subcutaneous injection by the calcium oxalate raphides
(Schmidt & Moult 1983). The irritant effects on the skin may be inhibited
by an antihistamine (Holzach & Flück 1951). Cases of an allergic contact dermatitis from black bryony have been
described by Milyavsky (1979) and Fernandez de Corres (1983). The rhizome and particularly the attractive scarlet berries can cause
poisoning when ingested. The symptoms are those of an irritant purgative
with burning of the mouth and blistering of the skin (North 1967, Lewis &
Elvin-Lewis 1977). Sources: |
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This page compliments of Marisa Ciceran Created: Saturdat,
September 03, 2005; Last updated:
Sunday, November 11, 2007 |
