Category: Current

Ganoderma applanatum 0

#070: Ganoderma applanatum, The Artist’s Conk

Ganoderma applanatum is unique among fungi in that it is primarily used by humans as an artistic medium. This large, woody bracket fungus features a mostly flat white pore surface that immediately stains brown when handled. Because of this, the mushroom readily becomes a natural canvas for an artist. By lightly scratching the pore surface, an artist can produce beautiful sketches without using a pen, pencil, or paint. The pores stop growing once the mushroom is removed from its substrate, so the stains remain on the pore surface. Conks produced by G. applanatum are woody and therefore decay very slowly. As a result, artwork produced on the Artist’s Conk can last for many years when dried and kept indoors.1,2 Description Ganoderma applanatum forms large conks, which are fan-shaped polypore mushrooms that grow shelf-like from dead logs. Conks are also known as bracket mushrooms or shelf mushrooms. The conks produced by...

207: Ergot Alkaloids 0

207: Ergot Alkaloids

Ergot Alkaloids (EAs) belong to a large class of mycotoxins. They are primarily produced by fungi in the genera Claviceps and Epichloë, although Claviceps purpurea is responsible for most of the impacts on humans. EAs are most common in rye, but can be found in any cereal grain. The toxins were a significant problem in the middle ages, but modern agricultural techniques mean that exposure to enough EAs to cause symptoms is extremely rare.1,2 Sources Many fungi produce ergot alkaloids in many different plant hosts. Humans are impacted most by species of Claviceps, which infect seeds of grasses. The most problematic species is C. purpurea (see FFF#061), which infects rye. A variety of other species infect cereal grains but cause less contamination. Livestock can be sickened by infected grain or by ergot alkaloids produced by endophytes in pasture grasses, most notably by Epichloë coenophiala.1–3 This post focuses on Claviceps and...

Amanita muscaria 0

#069: Amanita muscaria, Part 1: The Type Mushroom

You are undoubtedly familiar with this mushroom, even if you recognize neither its scientific name, Amanita muscaria, nor its common name, “The Fly Agaric.” If the word “mushroom” does not immediately bring this fungus to mind, then the word “toadstool” probably does. You have certainly encountered A. muscaria’s distinctive red cap with white spots in a variety of visual art forms. This toadstool frequently pops up in paintings, cartoons, video games, movies, and decorations. Essentially, A. muscaria is the default mushroom that people (in Western societies, anyway) think of when they hear the word “mushroom” – the type specimen for mushrooms, if you will. This is probably best illustrated by the Wikipedia page for “Mushroom,” which features a prominent picture of the photogenic Fly Agaric. Morphology Amanita muscaria produces large, umbrella-shaped agaric mushrooms with a circular, brightly colored pileus and a central, white stipe. The pileus ranges in size from...

Ochratoxin-producing molds 0

#206: Ochratoxins

Unlike most other mycotoxins found in food, the ochratoxins are primarily produced during food storage. Fungi in the genera Aspergillus and Penicillium are common molds that decompose a variety of foods, from grains to coffee to grapes. In the process, many of those fungi produce ochratoxins, which can damage the kidneys and cause cancer in many animals. Ochratoxins presumably impact humans the same way, but researchers have so far been unable to directly link ochratoxins to any human disease. This is probably because human consumption of ochratoxins is usually very low.