Wednesday, July 6, 2011

Plant and animal toxin

"All substances are poisons … The right dose separates a poison from a remedy." 


Toxicology-study of poisonous materials and their effects upon living organisms.
  • Toxins-a poisonous substance produced during the metabolism and growth of certain microorganisms and some higher plant and animal species.


Animal toxin - a toxin resembling bacterial toxins in its antigenic properties that is found in the fluids of certain animals.
Zootoxin- a  toxic substance of animal origin.
Venom- toxin secreted by animals; secreted by certain snakes and poisonous insects (e.g., spiders and scorpions).



  • Kissing bugs
All Kissing Bugs feed on blood, and those that prefer human blood can carry a serious disease. Charles Darwin's debilitating illness was probably caused by one.

Triatoma infestans is one of the Kissing Bugs. Like the ticks - (see how to remove them safely) - these bugs can carry human diseasesT.infestans is the most important carrier of Chaga’s disease in South America.
What happens is that the bug gets infected with the parasite (Trypanosoma cruzi) when he sucks blood from an infected person, and then passes it on when he bites a new victim. The parasite is actually passed out with the bug’s faeces, and then it creeps into the wound which is usually on the lips. Soon after infection there is a chronic reaction, typically with swelling around the lips, and then the disease lays dormant for several years. The later, chronic, stage of the disease is very serious. There is often severe heart damage, and while the disease can be treated just after infection, the chronic disease remains incurable. Even heart transplants don’t seem to work because the parasite just takes advantage of the lowered immune system, reproduces like mad, and then starts doing damage all over again!




  • Taricha granulosa



The rough-skinned newt (Taricha granulosa) is a North American newt known for its strong poison.
Many newts produce toxins to avoid predation, but the toxins of the genus Taricha are particularly potent. Toxicity is generally experienced only if the newt is ingested, although there are reports that some individuals experience skin irritation after dermal contact.The rough-skinned newt possesses tetrodotoxin, which in this species was formerly called tarichatoxin. This toxin binds reversibly to sodium channels in nerve cells and interferes with the normal flow of sodium ions in and out of the cell. This has the effect of inducing paralysis and death.




  • Rhinkals

The Rinkhals also called the Ringhals or Ring-necked Spitting Cobra (Hemachatus haemachatus) is a venomous elapid species found in parts of southern Africa. It is not a true cobra in that it is monotypic and does not belong in the genus Naja, but is closely related and is considered to be one of the true spitting cobras.Coloration varies throughout its distribution area but characteristic of the species is that the belly is dark and there are 1-2 light coloured crossbands on the throat. Average length is 90 - 110cm.Some individuals may have a mostly black body while others are striped. Rinkhals scales are distinct from that of true cobras in that they are ridged and keel-like.



Plant toxin - (Phytotoxin) any substance produced by plants that is similar in its properties to extracellular bacterial toxin.


  • Abrus precatorius



Abrus precatorius, known commonly as Jequirity, Crab's Eye, Rosary Pea, John Crow Bead, Precatory bean, Indian Licorice, Akar Saga, Giddee Giddee or Jumbie Bead in Trinidad & Tobago,[1] is a slender, perennial climber that twines around trees, shrubs, and hedges. It is a legume with long, pinnate-leafleted leaves. It is also known as Gunja in Sanskrit and some Indian languages and Ratti in Hindi. The plant is best known for its seeds, which are used as beads and in percussion instruments, and which are toxic due to the presence of abrin. The plant is native to Indonesia and grows in tropical and subtropical areas of the world where it has been introduced. It has a tendency to becomeweedy and invasive where it has been introduced.



  • Rhododendron

 
http://en.wikipedia.org/wiki/Rhododendron#Taxonomy 

Rhododendron (from Ancient Greek rhódon "rose", and déndron "tree")is a genus of over 1000 species of woody plants in the heath family, most with showy flowers. It includes the plants known to gardeners as azaleas. Rhododendron is a genus characterized by shrubs and small to (rarely) large trees, the smallest species growing to 10–100 centimetres (3.9–39 in) tall, and the largest, R. giganteum, reported to over 30 metres (98 ft) tall. The leaves are spirally arranged; leaf size can range from 1–2 cm (0.39–0.79 in) to over 50 cm (20 in), exceptionally 100 cm (39 in) in R. sinogrande. They may be either evergreen or deciduous. In some species the underside of the leaves is covered with scales (lepidote) or hairs (indumentum). Some of the best known species are noted for their many clusters of large flowers. There are alpine species with small flowers and small leaves, and tropical species such as section Vireya that often grow as epiphytes. Species in this genus may be part of the heath complex in oak-heath forests in eastern North America.


  • Hydrangea


Hydrangea ( /hˈdrnə/;[1] common names Hydrangea and Hortensia) is a genus of about 70 to 75 species of flowering plants native to southern and eastern Asia (China, Japan, Korea, the Himalayas, and Indonesia) and North and South America. By far the greatest species diversity is in eastern Asia, notably China, Japan, and Korea. Most are shrubs 1 to 3 meters tall, but some are small trees, and others lianas reaching up to 30 metres by climbing up trees. They can be either deciduous or evergreen, though the widely cultivated temperate species are all deciduous. 
Having been introduced to the Azores Islands of Portugal, they are now very common there, particularly on Faial Island, which is known as the "blue island" due to the vast number of hydrangeas present on the island, and on Flores Island. and Sao Miguel.
Species in the related genus Schizophragma, also in Hydrangeaceae, are also often known as hydrangeas. Schizophragma hydrangeoides and Hydrangea petiolaris are both commonly known as climbing hydrangeas.There are two flower arrangements in hydrangeas. Mophead flowers are large round flowerheads resembling pom-poms or, as the name implies, the head of a mop. In contrast, lacecap flowers bear round, flat flowerheads with a center core of subdued, fertile flowers surrounded by outer rings of showy, sterile flowers.


  • Nerium oleander

Nerium oleander (pronounced /ˈnɪəriəm ˈoʊliː.ændər/) is an evergreen shrub or small tree in the dogbane family Apocynaceae, toxic in all its parts. It is the only species currently classified in the genus Nerium. It is most commonly known as oleander, from its superficial resemblance to the unrelated olive Olea, but has many other names. It is so widely cultivated that no precise region of origin, perhaps in southwest Asia, has been identified. The ancient city of Volubilis in Morocco took its name from the old Latin name for the flower. Oleander is one of the most poisonous of commonly grown garden plants, and can be very toxic if ingested in sufficient quantity.
Oleander grows to 2–6 m (6.6–20 ft) tall, with erect stems that splay outward as they mature; first-year stems have a glaucous bloom, while mature stems have a grayish bark. The leaves are in pairs or whorls of three, thick and leathery, dark-green, narrow lanceolate, 5–21 cm (2.0–8.3 in) long and 1–3.5 cm (0.39–1.4 in) broad, and with an entire margin. The flowers grow in clusters at the end of each branch; they are white, pink to red, 2.5–5 cm (0.98–2.0 in) diameter, with a deeply 5-lobed fringed corolla round the central corolla tube. They are often, but not always, sweet-scented. The fruit is a long narrow capsule 5–23 cm (2.0–9.1 in) long, which splits open at maturity to release numerous downy seeds.
Oleander is one of the most poisonous plants in the world and contains numerous toxic compounds, many of which are deadly to people, especially young children. (Despite this fact, it is often grown in school yards.)
Pliny the Elder in his Naturalis Historia written circa AD 77 writes of this "rose-tree" (rhododendron)
It is a marvelous fact, but the leaves of this plant are poisonous to quadrupeds; whereas, for man, if taken in wine with rue, they are an effectual preservative against the venom of serpents. Sheep too, and goats, it is said, if they drink water in which the leaves have been steeped, will die immediately.
Ancient advice to counter poison with poison, like this, may often have deadly results, as Pliny's antidote would have.
Despite a lack of any proven benefits,a range of oleander-based treatments are being promoted on the Internet and in some alternative medicine circles, drawing a warning letter from the U.S. Food and Drug Administration (FDA). In addition, a Texas-based biotechnology company is researching oleander as a potential treatment for skin cancers, as well as an anti-viral treatment.
The toxicity of oleander is considered extremely high, and it has been reported that in some cases only a small amount had lethal or near-lethal effects.The most significant of these toxins are oleandrin and neriine, which are cardiac glycosides. They are present in all parts of the plant, but are most concentrated in the sap, which can block out receptors. High-risk circumstances of exposure include children playing with the ornamental shrub, as well as adults or children tasting, chewing, and ingesting portions of the plant, and inappropriate medicinal use of plant infusion.Oleander bark contains rosagenin, which is known for its strychnine-like effects. The entire plant, including the nectar, is toxic, and any part can cause an adverse reaction. Oleander is also known to hold its toxicity even after drying. It is thought that a handful or 10-20 leaves consumed by an adult can cause an adverse reaction, and a single leaf could be lethal to an infant or child. According to the Toxic Exposure Surveillance System (TESS), in 2002, there were 847 exposures to oleander reported to poison centers in the United States.There are innumerable reported suicidal cases of consuming mashed oleander seeds in southern India. Around 0.23 mg per pound of body weight is lethal to many animals, and various other doses will affect other animals. Most animals can suffer a reaction or death from this plant.




No comments:

Post a Comment