poisons fungi and plants Flashcards
posonous fungi(3)
fungal molds
fungal ergot
death cap
flowering plants (5)
monkshood poison hemlock water hemlock castor bean rosary pea
fungal molds
- aflatoxins- most dangerous of the fungal toxins
- serious health hazard
- agricultural products may be contaminated both before and following harvest
- toxins remain in food long after the fungus has died
- food is not visibly moldy
- corn, peanuts, cottonseed, rice, nuts, cereal, grains, and fruits
- aflatoxins from contaminated domestic animal feed are retained in eggs, milk and meat and so passes on to persons
- potent carcinogens- directly with DNA to strongly affect the transcription of genetic info
- children are particularly susceptible
fungal ergot
-fungal parasite of some cereal grains (rye), forage grasses, abundant in wet summers
-fungus attacks maturing cereal grains (purplish-black “fruiting bodies” known as schlerotia
-contaminated milled flour: baking does not destroy the poisoning alkaloids
-poising known as ergotism and st. anthony’s fire
-killed 40,000ppl
two types of egotism: gangrenous and convulsive
two major types of active alkaloids in ergot: ergonovine and LSD
gangrenous ergotism
- tingling sensation in the extremities, vomiting and diarrhea
- in a few days extremities become gangrenous, and hallucinations may be experienced
- eventually entire limbs are affected, resulting in excruciating pain as blood flow to the extremities declines, limbs eventually separate from the body
convulsive egotism
-this type produces painful uncontrolled spasms of the limb muscles, severe epileptic convulsions and eventually death
ergonovine and ergotamine
cause the arterioles (the fine arteries of the extremities) to contract
- contractions of smooth muscles tissue
- causes the the characteristic symptoms of ergotism: gangrene of the extremities, vomiting, muscle twitching and a staggering gait
Lysergic acid in ergotism
LSD
-produce visual-auditory hallucinations that are another reported symptom of ergotism
ergot poisoning and witchcraft
- most famous witch trial in puritan colony of salem massachusetts 1692
- a number of children and young adults experienced convulsions, mental disturbance and perceptual distortions that were attributed to witchcraft
- resulted in hanging of 20 ppl accused of demonic possesion
- salem witch trials- driven primarily by group hysteria, researchers say symptoms match those of ergotism
ergot history as medicine
- in europe it was carefully administered during childbirth to induce labour,
- it stimulates contractions of the uterine muscles
- used to control uterine hemorrhaging
death cap
a number of asidiomycete fungi are poisonous
- highly poisonous
- accounts for 90% of all mushroom poisoning fatalities
- there is a long ten hour latency period prior to the onset of poisoning symptoms
- the initial symptoms include abdominal cramping, nausea and vomiting and last for about a day
- apparent remission occurs the following day but is soon followed by severe intestinal pain as well as liver and kidney failure, death may occur if the patient is not immediately treated
- alkaloid amanitin- causes cell destruction
other poisonous mushrooms
-gymnomitra esculenta- poisoning by cell destruction
-entoloma sinatrum and boletus satanas- poinsoning by enteritis or inflammation of the small intestine
these are rarely mistaken for being edible
monkshood
- aka aconite
- buttercup family
- herbaceous
- ornamental plant
- deadly poison (all parts of plant are dangerous, especially the roots and tubers)
- alkaloid aconitine
- symptoms include- tingling and numbness of the muscles, a staggering gait, a crawling sensation on the skin, nausea and vomiting, laboured breathing and irregular pulse
poison hemlock
- carrot family
- herbaceous umbel
- socrates chose to be executed by drinking an infusion of poison hemlock
- pyridine alkaloids, including coniine- which stimulated and then paralyzes the nicotinic receptors of the CNS
- in large doses- powerful depressant, causing neuromuscular blockage, paralysis and dangerous lowering of blood pressure
- death may result from collapse of the cardiovascular sys
water hemlock
- genus cicuta
- apiaceae family
- three poisonous herbaceous species: c virosa, C. maculata and C. douglasii
- poison is an acetylenic alcohol called cicutoxin
- highest concentrations of circutoxin occur in the taproot, which resemblers a parsnip
- acts directly on the CNS
- poisoning occur within 30 minutes, include vomiting and convulsions, severe seizures, periodic cessation of breathing and at higher doses death
