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Cordyceps, the Zombie Fungus

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Bryony from the Visitor Team takes a look at the weird world of zombie fungi; a post originally on the ‘Stories from the Museum Floor’ blog

Stories from the Museum Floor

Today’s Story from the Museum Floor by Bryony from the Visitor Team takes a closer look at one of the most unusual objects from our botany collection.

And for more about plants, have a look at the Curator’s blog, Herbology Manchester.

Cordyceps, the Zombie Fungus

It’s Hallowe’en again, and you all know what that means… it’s our Stories from the Museum Floor Hallowe’en blog post, of course!

There are plenty of spooky things to write about in a museum. You might recall our post about the Death’s Head hawk moth, or perhaps the one about ancient Egyptian mummies … but would you expect to find … zombies?

Yes, we’ve got some real-life zombie specimens here in the museum. Now, brace yourselves, because this could get scary …

Cordyceps fungus on caterpillars, Nature’s Library, Manchester Museum. Cordyceps militaris is on the left, and Ophiocordyceps robertsii, right.

Don’t know…

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#BotanicMonday

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A few images from the herbarium recently

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Archives and labels are a gold mine of information in Herbarium collections #botanicMonday @Nat_SCA

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It’s #BotanicMonday and also #chocolateweek! Here’s a German teaching poster of the plant that produces the cocoa bean

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Plant models aplenty #BotanicMonday

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106 years old and still living up to its name – Showy pink oregano (Origanum sipyleum) #BotanicMonday

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Joanne B Kaar‏ @Joannebkaar Oct 15
More back rooms of @McrMuseum in herbarium @Aristolochia
photos from my recent research visit
packaging
labels
#lichen
I’m inspired

Object Lessons; Manchester Museum

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NatSCA

Most curators have those niggling objects at the back of their stores. Models and illustrations previously used for teaching or display in the dim and distant past, but kept for a rainy day. Not quite real objects and not the kind of thing you would necessarily want to accession.

Well, we’ve embraced these wonderful objects in our new exhibition: Object Lessons.

Brendel Models, George Loudon Collection Brendel Models, George Loudon Collection

Object Lessons celebrates the scientific model and illustration collection of George Loudon. Each of these finely crafted objects was created for the purpose of understanding the natural world through education, demonstration and display.

The object-rich exhibition will look at this incredible collection through themes such as Craftsmanship, the Teaching Museum and the Microscopic.

George’s collection will be displayed alongside stunning models from Manchester Museum and World Museum, Liverpool.

Here’s a selection of some of my favorites in the exhibition:

Octopus, Leopold and Rudolph Blaschka, Manchester Museum Octopus, Leopold…

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The Poison Chronicles: Calabar Bean – A Life-Saving Ordeal

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Calabar beans and seed cases from the collection of the Manchester Museum Herbarium. 

Guest Post by Laura Cooper

For much of human history, people have sought to find a way to prove or disprove a person’s guilt. Today, we hope evidence and a fair trial will do this, but people have always wanted a quick and definitive way of doing this. This is where the idea of the trial by ordeal came in. Most people are familiar with the practice of dunking suspected witches in bodies of water in parts of 17th century Europe; if they floated they were guilty and if they sunk they were innocent. But in what was then called the Calabar region (now North-East Nigeria) in the 19th century, a particularly poisonous seed was used in these trials by ordeal. This plant, known as the Calabar bean, Physostigma venenosum, became notorious as a poison. However, the principle lethal chemical of the Calabar bean, phystostigmine, was investigated by a number of physicians in Europe as an antidote to poisoning by atropine. Though both compounds can kill, their methods of murder are mirror images of each other, so that one can be used to cancel out the effects of the other; and so a poison can become a cure.

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Calabar beans from the Materia Medica collection of the Manchester Museum Herbarium. 

I can only find reports of the use of P. venenosum in ordeals in reports by Europeans visiting Calabar in 1846, who reported that 120 people died annually in the region by the Calabar bean. A person suspected of a misdeed would be made to consume the bean, likely soaked and crushed to release the toxins rather than whole. If they were guilty they would die, if they were innocent they would survive. It has been reported that swallowing the bean probably won’t result in death, but consuming a crushed seed would release toxins, like Abrus precatorius. Consuming enough seeds can lead to increased salivation, seizures, loss of control of urination and defectation and death by asphyxiation. Physostigmine has an oral LD50 (a dose which will kill half of a large group of mice) of 4.5 mg/kg, and the maximum number of beans reported eaten and survived is 35. Depending on a person’s weight and health, it is possible that one person may survive and another die after being given the same number of beans, and this difference can be attributed to their guilt or innocence.

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Image Source

The bean extract was known by medics in Europe, and extracts were used to constrict the pupil by ophthalmologists. Aware of it’s effects, in 1864 the Prague ophthalmologist Niemetschek suggested that a patient with atropine poisioning be given Calabar bean. Thomas Fraser investigated the effects of P. venenosum extract rigorously, and identified the chemical phystostigmine as the active chemical.

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Calabar beans from the Materia Medica Collection of the Manchester Museum Herbarium.

Phystostigmine acts as an acetylcholinesterase inhibitor. This means it prevents the neurotransmitter acetylcholine from being broken down, so the parasympathetic nervous system is continually stimulated. This is the exact opposite effects of atropine, an anticholinergic drug derived from Atropa belladonna, which I have written about before. Atropine causes anticholinergic syndrome, making the patient “dry as a bone, blind as a bat, red as a beet, mad as a hatter, hot as a hare”, as medical students remember it.

But many other chemicals and conditions can cause anticholinergic syndrome, and despite many published cases of phystostigmine being used to treat anticholinergic syndrome safely and effectively, it has been reported as being underused. It could be speculated that this underuse could be due to the gruesome reputation of the source of the chemical, the Calabar bean, and therefore a hesitancy to recommend the drug. But whilst the drug is dangerous at a high enough dose, the ordeals themselves show that it is survivable (if you are innocent, that is!). We return again to the common theme of plant poisons; everything has a lethal dose, even water, what is more interesting is what doses lower than this can do to the human body.

The Poison Chronicles: Deadly Nightshade

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Atropa belladonna model from the Manchester Museum Herbarium

Guest Post by Laura Cooper

Binomials can be a pain to learn, but they often have a hidden poetry. Deadly nightshade’s common name stresses its notoriety as a poison. But it’s binomial, Atropa belladonna, is far more beautiful and apt. The genus name is derived from Atropus, one of the three Fates of Greek Mythology, whose shears could cut the threads of life. The species name belladonna is the Italian for beautiful woman, named so because of the plant’s use in giving pleasingly dilated pupils. A figurative translation of the name could be femme fatale, appropriate for a plant whose main danger to humans is to the forager lured to pick and eat the glossy black berries.

The Herbarium has a large model of these berries displayed on a cabinet in the main room. It caught my eye as I was returning the gloves I wore to find Atropa belladonna Herbarium sheets. Compared to the shriveled fruits I had just seen, this was a regal fruit with the sepals like a ruff and a grandly arching stem. A belladonna indeed.

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Finding Atropa belladonna Herbarium sheets in the Manchester Museum Herbarium

Atropa belladonna is one of the most common plants involved in poisoning throughout most of Europe and central Asia, but is still no minor threat. For example, the plant topped the list of plants causing severe poisoning in Switzerland between 1966-1994. Of a total of 24,950 cases of contact with poisonous plants, 135 cases (0.6% of total) were serious poisonings with sufficient information. Atropa belladonna was involved in 42 of these cases, but no deaths were reported. This doesn’t mean the plant should be treated lightly though. It has the potential to be quite dangerous.

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Atropa belladonna Herbarium sheet showing the fruit, from the Manchester Museum Herbarium

As with many poisonous plants, it is very difficult to get an accurate measure of the lethal dose. Some report that an adult would be killed by 10-20 berries, whilst others report a case of children who had eaten eaten up to 40 berries and survived after hospitalisation.

A. belladonna‘s deadly potential is principally derived from three toxins, the tropane alkaloids hyoscine, hyoscyamine and atropine. The toxins have an anticholinergic effect, which means they affect neurones by competing with the neurotransmitter acetylcholine for muscarinic receptors. After a delay, this leads to an inhibition of the parasympathetic nervous system. This produces anticholingeric syndrome, whose symptoms are remembered by the mnemonic, “dry as a bone, blind as a bat, red as a beet, mad as a hatter, hot as a hare”. If the dose is high, this can lead to psychosis, convulsions, respiratory failure and death.

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Atropa belladonna Herbarium sheet showing flowers, from the Manchester Museum Herbarium

 A. belladonna and its derivatives were favoured tool for the poisoner. In the late 19th century, the psychopathic American nurse Jane Toppan used atropine in concert with morphine to kill over 31 people. As atropine and morphine produce opposite responses, atropine “speeds up” the system whilst morphine slows down the body, Toppan balanced the doses of both drugs to prolong her victims’ struggle until a fatal dose was given.

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Atropa belladonna poster from the Manchester Museum Herbarium

However, atropine in the right hands can be a very useful chemical, even a lifesaver. It is the standard antidote for nerve gas poisoning, as it blocks the excess acetylcholine the nerve gas produced. It is also used to dilate eyes for examination by an ophthalmologist and is given to patients after cardiac arrest. Ironically, the very “poison” that Jane Toppan used to kill a victim whose death was originally recorded as heart disease is now used to help save patients from dying from a heart attack. There can always be a useful side to the proverbially deadliest of plants.

The Travelling Botanist: Cinnamon, a spice of many tales

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Guest blog by: Sophie Mogg

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Cinnamomum cassia

Cinnamon is a spice that we have all had the opportunity to try, whether in fancy coffees, liqueurs or delicious buns. Whilst the “true” cinnamon species is Cinnamomum verum, the most common source of cinnamon is Cinnamomum cassia. Both species originate in Asia, with C. verum being native to Sri Lanka (formerly known as Ceylon) and C. cassia originating in southern China. In order to distinguish the cinnamon produced by the two species in the spice trade, cinnamon refers to C. verum whilst cassia refers to C. cassia.  This is because, C. verum is  more expensive of the two due to its sweeter taste and aroma as less than 30% of cinnamon exports come from Sri Lanka. 

Cinnamon has been traded for many thousands of years, with the imports into Egypt reported as early as 2000 BCE so it is no surprise that there are countless tales and historical events that surround this spice. From Sieur de Joinville believing cinnamon was fished from the Nile at the end of the world and Herodotus writing about mystical giant birds (such as a phoenix) that used cinnamon sticks to build their nests, the history of cinnamon is rich in legends of its origin as it wasn’t until 1270 that it was mentioned the spice grew in Sri Lanka. However as sweet as this spice may be it also appears to have a bloody history. Aside from the countless wars raged over the right to trade cinnamon, it was also used on the funeral pyre of Poppaea Sabina, the wife of Nero, in 65 AD. It is said that he burned over a years supply as recompense for the part he played in her death.

There are a total of 5 species (C. burmannii, C. cassia, C. citriodorumC. loureiroi and C. verum)  that produce cinnamon however C. verum and C. cassia are where the majority of international commerce is sourced from. Production of cinnamon is fairly straight forward albeit time-consuming. The outer bark of the tree is shaved off exposing the inner bark which is the cinnamon layer. This inner bark is also shaved off and left to dry, naturally curling as it does. By comparison the cinnamon of C. verum has a more delicate flavour than that of C. cassia  as well as having thinner bark that is more easy to crush and produces a much more smooth texture. cinnamon-comparison

Cinnamon is prominent in the practice of Ayurveda medicine as well as traditional Chinese medicine, being one of the 50 fundamental herbs. Traditionally it has been used to treat a wide variety of ailments from digestive problems, respiratory problems, arthritis and infections. In traditional Chinese medicine it is believed that cinnamon is able to treat these ailments through it’s ability to balance the Yin and Wei as well being a counterflow for Qi. These terms are aptly explained here for those who are interested. While there is little scientific evidence for the treatment of digestive and respiratory disorders, cinnamon does appear to possess antibacterial, antifungal and antimicrobial properties which may help to fight infections although at this moment in time it is inconclusive in studies trialled on humans. Cinnamon produced from C. cassia coumarin, which thins the blood, can be toxic to the liver in high concentrations so it is advised that only a few grams per day be consumed.

For those avid tea lovers out there I’ve found instructions to brew your own cinnamon tea.

For more information check out the links below

Cinnamomum verum

Cinnamomum cassia in Chinese medicine

Rainforest Alliance – Cinnamon farms

Leave a comment below to tell me what you think or what you’d like to see next!