Chemistry, biological activity and toxicity of Australian fungi
Fungi contain many interesting chemical compounds that have a variety of potential uses, but can also cause danger when wild fungi are consumed for food.
Chemicals in fungi often have a role in the life of the fungus in its natural environment. Some fungi produce anti-bacterial and anti-fungal compounds that presumably assist in making space for the particular fungus in the crowded soil environment, which can contain numerous species of fungi and bacteria in relatively small areas. Saprotrophic (decay) fungi have an array of enzymes that can break down complex organic molecules such as lignin and cellulose and also polymers such as polyurethane.
The biological activities of fungi can be harnessed for human good, such as by using the chemical structures present in nature as a basis for synthesising medicines. Medicines sourced from fungi include antibiotics (penicillin, cephalosporin), anti-fungal agents (griseofulvin), ergot alkaloids, statins, and immune suppressants (cyclosporin). Some fungi contain compounds that are being investigated for anti-cancer activity.
Biological activity of fungi also has many industrial applications. Yeasts are a type of fungus, and are widely used in fermentation for production of wine, beer and bread. Enzymes derived from fungi are utilised to produce 'stone-washed' denim. Fungi also have promising applications in bioremediation, especially for degradation of various organic substrates, such as in paper recycling, cleaning up of petrochemical spills and decolourisation of tannins in water.
Royal Botanic Gardens Melbourne mycologists carry out collaborative research on fungi that contain chemicals, from the point of view of taxonomy, toxicity and biological activity. The role of the mycologist is to collect and identify fungi of interest to chemists and pharmacologists. Knowledge of evolutionary relationships of fungi, such as from parallel studies of molecular phylogeny, can guide sampling for target chemicals.
A particular focus of this multidisciplinary research is on fungal systematics and chemistry is the genus Cortinarius, a common genus of agarics (gilled fungi). Some species of Cortinarius are brightly coloured due to anthraquinone pigments. Many of these pigments have novel structures, and some have high antibiotic activity. Pigments can be visualised by thin-layer chromatography, and the presence or absence of certain pigment bands is useful for taxonomy at the species level.
In addition to medical and industrial uses, chemical compounds in fungi can impart pleasant flavours that make wild and cultivated mushrooms attractive as food. However, some fungi contain highly toxic chemicals that can lead to serious illness or death on ingestion.
Mycologists are on call to handle enquiries about identification of poisonous fungi, and also collect data on the species responsible for poisonings. Most human poisonings are caused by adults mistaking poisonous for edible fungi, such as when consuming Yellow Stainer (Agaricus xanthodermus) when the intended species is Field Mushroom (Agaricus campestris). Young children often eat or appear to eat mushrooms, but this rarely result in poisoning, because the fungi are a random sample from the fungi that grow in home gardens and parks, such as harmless species ofCoprinus and Psathyrella. Because the aptly named Death Cap (Amanita phalloides) occurs in Australia, it is important to provide a rapid response to enquires about potentially poisonous fungi.
- Tom May (Royal Botanic Gardens Melbourne)
- Evelin Tiralongo (School of Pharmacy, Griffith University)
- Joe Tiralongo (Institute for Glycomics, Griffith University)
- Karren Beattie (School of Health and Human Sciences, Southern Cross University)
- Jeff Robinson (Victorian Poisons Information Centre)
- Dawson McLeod (Victorian Poisons Information Centre)
Beattie, K.D., Thompson, D.R., Tiralongo, E., Ratkowsky, D., May, T.W. and Gill, M. (2011) Austrocolorone B and austrocolorin B1, cytotoxic anthracenone dimers from the Tasmanian mushroom Cortinarius vinosipes Gasparini.Tetrahedron Letters 52, 5448–5451.
Jones, R.H. and May, T.W. (2008). Pigment chemistry and morphology support recognition of Cortinarius austrocinnabarinus sp. nov. (Fungi: Cortinariaceae) from Australia. Muelleria 26, 77–87.
Ovenden, S.P.B., Yu, J., Bernays, J., Wan, S.S., Christophidis, L.J., Sberna, G., Tait, R.M., Wildman, H.G., Lebeller, D., Platel, D., May, T.W. and Meurer-Grimes, B.M. (2005). Trichomycins A and B: antibacterial triterpenes from the new species Tricholoma sp. AU1. Journal of Natural Products 68, 409–412.
Watling, R., Gill, M., Giménez, A. and May, T.W. (1992). A new styrylpyrone-containing Cortinarius from Australia. Mycological Research 96, 743–748.
Rouf, R., Tiralongo, E., Krahl, A., Maes, K., Spaan, L., Wolf, S., May, T.W. and Tiralongo, J. (2011). Comparative study of hemagglutination and lectin activity in Australian medicinal mushrooms (higher Basidiomycetes). International Journal of Medicinal Mushrooms. 13, 493–504.
Beattie, K.D., Ulrich, R., Grice, I.D., Uddin, S.J., Blake, T.B., Wood, K.A., Steele, J., Iu, F., May, T.W. and Tiralongo, E. (2011). Ethanolic and aqueous extracts derived from Australian fungi inhibit cancer cell growth in vitro.Mycologia 103, 485–465.
Beattie, K.D., Raouf, R., Gander, L., May, T.W., Ratkowsky, D., Donner, C.D., Gill, M., Grice, I.D. and Tiralongo, E. (2010). Antibacterial metabolites from Australian macrofungi from the genus Cortinarius. Phytochemistry 71, 948–955.
Solarska, S., May, T., Roddick, F.A. and Lawrie, A.C. (2009). Isolation and screening of natural organic matter-degrading fungi. Chemosphere 75, 751–758.
Robinson, J.P., MacLeod, D.S., Taylor, D.M., Lebel, T. and May, T.W. (2006). The safety of edible fungi purchased at Melbourne markets. Australianand New Zealand Journal of Public Health 30, 279–280.
Hender, E.A., May, T.W. and Beulke, S.H. (2000). Poisoning due to eating fungi in Victoria. Australian Family Physician 29, 1000–1004.