Datura stramonium
Datura stramonium, known by the common names thornapple, jimsonweed, or devil's trumpet, is a poisonous flowering plant in the Daturae tribe of the nightshade family Solanaceae. Its likely origin was in Central America, and it has been introduced in many world regions. It is an aggressive invasive weed in temperate climates and tropical climates across the world. D. stramonium has frequently been employed in traditional medicine to treat a variety of ailments. It has also been used as a hallucinogen, taken entheogenically to cause intense, sacred or occult visions. It is unlikely ever to become a major drug of abuse owing to effects upon both mind and body frequently perceived as being highly unpleasant, giving rise to a state of profound and long-lasting disorientation or delirium with a potentially fatal outcome. It contains tropane alkaloids which are responsible for the psychoactive effects, and may be severely toxic.
Description
Datura stramonium is an erect, annual, freely branching herb that forms a bush tall.The root is long, thick, fibrous, and white. The stem is stout, erect, leafy, smooth, and pale yellow-green to reddish purple in color. The stem forks off repeatedly into branches and each fork forms a leaf and a single, erect flower.
The leaves are about long, smooth, toothed, soft, and irregularly undulated. The upper surface of the leaves is a darker green, and the bottom is a light green. The leaves have a bitter and nauseating taste, which is imparted to extracts of the herb, and remains even after the leaves have been dried.
Datura stramonium generally flowers throughout the summer. The fragrant flowers have a pleasing odour; are trumpet-shaped, white to creamy or violet, and long; and grow on short stems from either the axils of the leaves or the places where the branches fork. The calyx is long and tubular, swollen at the bottom, and sharply angled, surmounted by five sharp teeth. The corolla, which is folded and only partially open, is white, funnel-shaped, and has prominent ribs. The flowers open at night, emitting a pleasant fragrance, and are fed upon by nocturnal moths.
The egg-shaped seed capsule is in diameter and either covered with spines or bald. At maturity, it splits into four chambers, each with dozens of small, black seeds.
Etymology and common names
The genus name is derived from the plant's Hindi name,, ultimately from Sanskrit, 'white thorn-apple'. The origin of Neo-Latin stramonium is unknown; the name Stramonia was used in the 17th century for various Datura species. There is some evidence that Stramonium is originally from Greek strychnos, 'nightshade' and μανικόν, 'which makes mad'. It is called in Telugu, and in Tamil.; both of which are believed to have derived from the Sanskrit word , meaning 'mad' or 'insane'.In the United States, the plant commonly known as "Jimsonweed". This name derives from Jamestown, Virginia, where soldiers sent to suppress Bacon's Rebellion in the English colony of Virginia reportedly consumed the plant and spent eleven days in altered mental states:
Common names for Datura stramonium vary by region and include thornapple, moon flower, hell's bells, devil's trumpet, devil's weed, tolguacha, Jamestown weed, stinkweed, locoweed, pricklyburr, false castor oil plant, and devil's cucumber.
Range and habitat
Datura stramonium is native to Central America, but was spread widely to the Old World early where it has also become naturalized. It was scientifically described and named by Swedish botanist Carl Linnaeus in 1753, although it had been described a century earlier by botanists such as Nicholas Culpeper. Today, it grows wild in all the world's warm and temperate regions, where it is found along roadsides and at dung-rich livestock enclosures. In Europe, it is found as a weed in garbage dumps and wastelands, and is toxic to animals consuming it. In South Africa, it is colloquially known by the Afrikaans name malpitte.Through observation, the seed is thought to be carried by birds and spread in their droppings. Its seeds can lie dormant underground for years and germinate when the soil is disturbed. The Royal Horticultural Society has advised worried gardeners to dig it up or have it otherwise removed, while wearing gloves to handle it.
Toxicity
All parts of Datura plants contain dangerous levels of the tropane alkaloids atropine, hyoscyamine, and scopolamine, all of which are classified as deliriants, or anticholinergics. The risk of fatal overdose is high among uninformed users, and many hospitalizations occur among recreational users who ingest the plant for its psychoactive effects. Deliberate or inadvertent poisoning resulting from smoking jimsonweed and other related species has been reported. Numerous other alkaloids have been detected at lower levels in the plant including methylecgonine in the roots, apoatropine in the stems, leaves, and other parts, and tropine in the flowers and other parts.The amount of toxins varies widely from plant to plant. As much as a 20:1 variation can be found between plants, and a given plant's toxicity depends on its age, where it is growing, and the local weather conditions. A particularly strong difference has been found between plants growing in their native ranges and plants that have adjusted to growing in non-native ranges: in the latter, the atropine and scopolamine concentration may be up to 20–40 times lower than in the native range. It is suspected that this is an evolutionary response to lower predatory pressures. Additionally, within a given plant, toxin concentration varies by part and even from leaf to leaf. When the plant is younger, the ratio of scopolamine to atropine is about 3:1; after flowering, this ratio is reversed, with the amount of scopolamine continuing to decrease as the plant gets older. In traditional cultures, a great deal of experience and detailed knowledge of Datura was critical to minimize harm. An individual seed contains about 0.1 mg of atropine, and the approximate fatal dose for adult humans is >10 mg atropine or >2–4 mg scopolamine.
Recently a rodent study investigating a methanolic extract derived from the whole plant reported significant behavioural and neurochemical effects. The extract induced memory deficits, along with anxiogenic and depressive-like behaviours. These effects were associated with elevated lipid peroxidation and a marked depletion of antioxidant enzymes in the brain. Histological analysis revealed disrupted neuronal morphology in the hippocampus and medial prefrontal cortex, providing evidence suggestive of the plant's neurotoxic potential.
Datura intoxication typically produces delirium, hallucination, hyperthermia, tachycardia, bizarre behavior, urinary retention, and severe mydriasis, with resultant painful photophobia that can last several days. Pronounced amnesia is another commonly reported effect. The onset of symptoms generally occurs around 30 to 60 minutes after ingesting the herb. These symptoms generally last from 24 to 48 hours, but have been reported in some cases to last as long as two weeks.
As with other cases of anticholinergic poisoning, intravenous physostigmine can be administered in severe cases as an antidote.
Natural defenses
These chemical production responses present in Datura stramonium function as a natural defense for the plant against dangers. Such dangers can range from biotic factors such as herbivores, pathogens, viruses, fungi and oomycetes to abiotic conditions such as drought, light, temperature, and nutrient deprivation. Datura stramonium can adjust to all these conditions through protein activity that is correlated with specific domains. Examples of this are terpenoid production to target herbivores present in multiple sites and abiotic stress responses. The abiotic responses are driven primarily by protein kinase regulatory subunits which are over-represented, expanded, and positively selected. These traits also show signs of physicochemical divergence, which put emphasis on the plant's overall adaptability. In addition to this, terpenoids play a key role in mediating plant defense responses, as they trigger terpene metabolite activity. Such activity has the effect of defending against herbivore damage through a sulfakinin domain that reduces sensitivity of taste receptors for certain insects that come into contact with the plant. Additionally, terpenoids serve as attractants for carnivorous entities that would then attack these same herbivores. Gene domains relating to this immune response have been seen in positively selected and expanded proteins in Datura stramonium. Overall, these compounds target the central nervous systems of organisms that ingest them, to deter the herbivorous behavior. Terpenoids are also used for plant-to-plant communication, which could be used for a community-wide threat response. Datura stramonium also features leaf trichomes as a defensive trait to prevent herbivory.The physiology of the plant itself is important for understanding patterns of defense as its status as an annual plant limits opportunities for biomass regrowth post-destruction, due to its inability to engage regrowth meristems. This results in the leaves being susceptible to injury from even small instances of attacks. To compensate, they have a large initial size for redundancy. These leaves also have a greater longevity and ability to metabolize even when damaged. However, the way these plants have evolved to display these characteristics differs from traditional defense mechanisms, as Datura stramonium uses a combination of both resistance and growth simultaneously to address these issues, instead of relying exclusively on one or the other. It has been hypothesized that this is due to the fact that these two methods have no negative correlation between them in experimental conditions. However, resource limitations may result in a tradeoff between one method of defense versus the other. In addition, herbivores are not solely the driving force that triggers these responses within the plant. Another factor that impacts behavior is the fact that due to the wide habitat range, a number of different, region-specific response patterns have been observed. However, these defensive responses have been observed to have varying impacts on growth and fitness when put to the test against predators. Studies in ecological reserves have shown that herbivore presence can either increase or decrease plant growth, fitness, and resistance. These results can be attributed to the significant genetic variation of the individual variants present in testing.