Introduction to poisonous plants of the genus Bryonia
The gender bryonia It is widely recognized in botany and toxicology due to the intense poisonous properties of its most representative species, such as bryonia alba, Bryonia dioica, Bryonia cretica y Bryonia verrucosaThese climbing plants, belonging to the family cucurbitaceae, have played an important role in both popular culture and traditional medicine, but they also pose a danger to human and animal health due to their content of potent toxic substances.
Taxonomy and species of the genus Bryonia
The gender bryonia It belongs to the kingdom Plantae, division Magnoliophyta, class Magnoliopsida, order Cucurbitales, and family Cucurbitaceae. Among the most representative and studied species are:
- bryonia alba (white alfesir or white walnut)
- Bryonia dioica (tuca, red walnut, red walnut)
- Bryonia cretica (walnut, devil's cabbage, devil's pickle)
- Bryonia verrucosa (poison, Canarian endemic)
Each of these species has morphological, ecological, and toxic characteristics that merit detailed attention.
Morphology and general characteristics
- Growth forms: All species of Bryonia are climbing plants Perennials, with thin, fibrous and highly branched stems, capable of reaching several meters in length through the use of simple spiral tendrils that allow them to cling to other plants or structures.
- Sheets: Of alternate arrangement, with palmate or deltoid limbus that usually shows between 3 and 7 lobes, and a deeply serrated edge. They have a rough feel due to the presence of hairs and, in some species such as Bryonia verrucosa, are warty to the touch.
- Flowers: Small, unisexual flowers, white, greenish or pale yellow. In some species, such as B. dioica y B. verrucosaThe plants are dioecious (with male and female flowers on separate individuals). They bloom in spring and summer.
- Fruits: Its globose berries between 1 and 3 cm in diameter. The color varies depending on the species and the degree of ripeness: bright red or orange in B. dioica and black in B. alba. The unripe fruits are green with pale stripes.
- Root: These plants have tuberous roots, perennial and voluminous, from which annual stems sprout every spring.
They stand out for their rapid growth and their ability to cover large areas, being Common in hedges, borders, forests, thickets, roadsides and limestone rocky areas with a preference for well-drained soils.
Habitats and distribution
The different species of bryonia They have a Eurasian and North African distribution, with variable ecological preferences:
- B. alba: Common in central, eastern and southern Europe and widely naturalized in other temperate regions, including cultivated areas and wilderness areas.
- B. dioica: It is prevalent in Western Europe, especially in humid areas of forest, scrubland, hedgerows, riverbanks and cultivated fields.
- B. cretica: Native to the Mediterranean basin, adapted to rocky slopes, open forests and field margins.
- B. verrucosa: Endemic to the Canary Islands, present in xerophytic scrub and thermophilic forests at low and medium altitudes, occupying large areas of land alone.
Its flowering and fruiting season varies slightly between species and regions, but usually covers the warmer months of the year.
Toxic active ingredients and mechanism of toxicity
The bryonia They are considered extremely poisonous plants due to the presence of several toxic compounds, mainly:
- Cucurbitacins: Tetracyclic triterpenes responsible for most of the toxic effects (purgative, emetic, vesicant and cytotoxic action).
- Brionina: Toxic glycoside that affects both humans and animals.
- Brionycin, bristesin and brioresin: Alkaloids and resins with purgative and toxic effects.
- Cucurbitacin heterosides such as briodulcoside, brioside, brionoside and brioamarid, with marked irritant action.
These substances are found in all parts of the plant, with the fruits and roots being the most dangerous. Accidental consumption can be fatal, especially for children and pets. Toxicity also affects livestock if they consume the leaves or fruits.
Clinical picture and symptoms of poisoning
- By ingestion: Symptoms appear between one and four hours after ingestion and include Severe vomiting, abdominal cramping pain, profuse diarrhea, hyperdiuresis and fast dehydrationIn severe cases, they can be added vertigo, excitability, seizures and respiratory collapse.
- By skin contact: The sap and milky juice of stems and roots can cause urticarial irritations, redness, blistering and even skin necrosis, especially if there is prolonged contact.
- In adults: A lethal dose is estimated to be between 40 to 50 ripe berries.
- In children: Just 15 berries can be fatal, and smaller amounts can also cause severe poisoning.
Deaths are usually due to respiratory paralysis o intestinal bleedingSymptoms of severe poisoning include cholera-like diarrhea, internal bleeding, and nephritis.
Treatment of Bryonia poisoning
- By skin contact: Wash the affected area with plenty of water, apply cold compresses, and apply antihistamine creams to relieve pain and inflammation. Skin lesions usually resolve within a few hours.
- By ingestion:
- Perform gastric emptying if time permits (gastric lavage or emetics, as directed by a doctor).
- Immediate contribution of fluids and electrolytes to prevent dehydration and replace digestive and urinary losses.
- Life support: Maintain respiratory and cardiocirculatory function if necessary.
- Ante excitement or convulsions, use sedatives such as benzodiazepines under medical supervision.
Early medical attention is essential if you suspect poisoning from plants of the Bryonia genus.
Traditional uses, medicine and warnings
- Traditional medicine: Historically, different parts of the plant (especially roots and leaves) have been used as purgatives, emetics, antirheumatics and analgesicsAn example is the use of tuca in poultices to treat sciatica, rheumatism or low back pain.
- Ancient Pharmacology: Quotes from Dioscorides and its use in Europe and the Mediterranean to combat various ailments, although its use was abandoned due to the high risk of poisoning.
- Modern properties studied: The cucurbitacins They have received attention in recent studies for their possible anticancer and antifungal properties, and for being inhibitors of cell adhesion in tumor lines, but the plant should not be used without medical supervision.
- Culinary and food: In some areas, the tender shoots They have been consumed after removing the tendrils, although their use is not recommended due to the toxicity of the entire plant.
Today, the marketing of all parts of Bryonia is strictly prohibited or restricted due to its high toxicity.
Identification and common confusions
La correct identification Bryonia is essential to avoid poisoning. In autumn, when only the fruits remain on dry stems, it can be confused with Tamus communis, which lacks tendrils and whose seeds are spherical, but does not have the same arrangement of leaves and fruit.
Curiosities and cultural uses
- Superstition and magic: It is said that Emperor Augustus wore a toucan crown to protect himself from lightning during storms.
- Veterinary and ethnobotany: The plant was used in the past as a purgative for animals and to treat skin diseases.
- Protection and conservation: Some species like Bryonia verrucosa They are protected due to their endemic nature and risk of extinction.
Common names
Plants of the genus Bryonia receive numerous popular names in different regions: fight, walnut, devil's cabbage, walnut asparagus, poison, snake vine, dog grapes, zarzaparrilla and many others, reflecting its wide distribution and cultural roots.
Prevention and safety tips
- Do not consume any part of the plant if there is no complete assurance of its safety and medical control.
- Avoid skin contact, especially if there is a history of allergies or sensitivities.
- Prevent access by children and pets to areas where these plants are located, due to the risk of accidental poisoning.
- Consult a specialist at the slightest doubt in the identification or suspicious symptoms.
Poisonous plants of the genus Bryonia are an outstanding example of how nature can endow plant species with extremely effective defense mechanisms. Their beauty and ruggedness should not deceive: improper handling or consumption can have fatal consequences. Knowledge of their characteristics, toxicity and properties is essential to avoid risks and conserve natural heritage., especially in those endemic or protected species.
