Fungal protein foods can compete successfully with animal protein foods like meat on health grounds:
good content of protein (20-30% of dry matter) that contains essential amino acids
chitinous walls as a source of dietary fibre
contain B-vitamins
low in fat
virtually free of cholesterol

Because fungal foods can be produced using waste products as substrates, they should also be able to compete successfully on grounds of primary cost.

Industry produces wastes...
Oyster and paddy straw mushrooms grow well on cotton waste of textile and garment industries

Agriculture produces wastes...
Typically, 80 to 90% of the total biomass of agricultural production is discarded as waste. For example, in 1995 the global production of cereal straw was estimated at 3.2 × 109 metric tonnes
And not just cereals. All agricultural production generates enormous waste because so little of each crop is actually used: 95% of the total biomass produced in palm and coconut oil plantations is discarded as waste, 98% of the sisal plant is waste, 99.8% of coffee biomass is waste, 83% of sugar cane biomass is waste. So, from this entire field of rape (canola) only the oil from the seeds will be used.

This is an unacceptable loss of primary production but we could grow a lot of fungi on agricultural residues and convert wastes into food, animal feed, pharmaceuticals and other products.

Opportunities for the twenty-first century - themes for exploitation

use of substrates that are waste products from other industries

combining bioremediation with mushroom crop production

leading to sustainable use of a wider range of the biodiversity evident in natural populations

It’s an attractive notion to use the fungus to digest the waste and by so doing produce a cash crop of mushrooms. Even more attractive is that after the mushrooms have been harvested the ‘spent compost’ can be a useful:

animal feed (the mushroom mycelium boosts its protein content),

soil conditioner (it is a compost still rich in nutrients and with polymeric components
that enhance soil structure)

and even used to digest pollutants (like polychlorinated phenols) on land-fill waste sites
because it contains populations of microorganisms able to digest the natural phenolic
components of lignin.

Many wastes are hazardous because they contain tannins and phenolics, toxic to plants and animals:

residues from extraction of oils such as cotton, rape, olive, palm oils;

fruit processing residues, such as citrus wastes;

wastes contaminated with pesticides.

Bioremediation with fungi

Several cultivated mushrooms (e.g. Pleurotus and Lentinula species) can degrade lignin in plant litter. And these enzymes detoxify phenolic residues as well. Producing a crop of mushrooms whilst disposing of an otherwise hazardous waste has become a popular ‘research model’ in recent years. Pleurotus cultivation may even aid removal of pollutants from landfill or contaminated waste sites.

Bioremediation with Pleurotus: the spent compost is able to remove the biocide pentachlorophenol (PCP) very effectively.

PCP has been the most heavily used pesticide throughout the world; it is very persistent in the natural environment and a common cause of soil contamination. Using spent mushroom substrates in landfill sites combines soil conditioning with degradation of organopollutants as an effective strategy for bioremediation in situ.

Heavy metal warning ...

Care is needed because mushrooms accumulate metal ions. Wastes gathered from industrial sources for use in mushroom compost may be contaminated by heavy metals.

Cadmium content in experimental Pleurotus fruit bodies reached 0.03 mg g-1 dry wt.

FAO/WHO recommend weekly intake of cadmium by adult humans should not exceed 
0.4 - 0.5 mg;

only 20 g (dry weight) of heavily contaminated oyster mushroom (which do not show any 
abnormality in appearance) would exceed this level.

Cadmium poisoning causes kidney, liver and skeletal disorders.

Regular monitoring of the metal contents of edible mushrooms produced in bioremediation programmes is highly recommended!

The non-green revolution

One thing we must do is make better use of what the Earth already produces. On average, agriculture currently loses 40% of its PRIMARY PRODUCTION to pests and diseases and then throws away more than 70% of what’s left because the crop always represents so little of what is grown. That works out to an overall 18% efficiency, at best. Fungi, especially the mushroom fungi, are ideal candidates to degrade waste vegetation, including any polluted with pesticides. Many pesticides are chemically similar to the complex phenolic compounds found in wood and because the fungi can decompose wood, they can also be used to degrade ENVIRONMENTAL POLLUTANTS in soils and wastewater discharges.

Wake up to fungi!

Arguably, the first higher organisms to evolve, in a sense fungi gave rise to plants and animals, maybe 2 billion years ago. Later, they enabled plants to invade the land to start terrestrial development of planet Earth, helping the plants to shape nature as we know it today. We would not be here without fungi because their interventions and contributions have been crucial in the development of life on land to the point where it could support larger animals. And all the while, the fungi themselves were so well adapted to even dramatically changing environments that their own evolution was slow and relaxed.

Wake up to fungi!
A new book about fungi for the general reader:

SLAYERS, SAVIORS,

SERVANTS and SEX

An Exposé of Kingdom Fungi

by DAVID MOORE

This is a book for the general reader about the world of fungi. We should know more about fungi. They have killed us, saved us and served us since before written records began. We have been making bread, brewing ale, and fermenting wine for millennia. Our crops have been at the mercy of fungal diseases since we became farmers, and they still are. Fungal diseases have caused large demographic changes - from the great plague of "St. Anthony’s Fire" of the Middle Ages (caused by a fungal toxin) to the Irish mass migration to the Americas during the famine (caused by a fungal disease of the potato crop).

We can also thank fungi for antibiotics, but do we fully appreciate the revolution in life style (and life expectancy) that these taken-for-granted treatments permit? One of the first people to receive penicillin treatment in England in the 1940s was a policeman in Oxford. He died of septicemia when the supplies of the antibiotic ran out. Cause of death? Scratched by a rose thorn!

Fungi enabled plants (by a mutualistic combination that persists today) to invade the land during the evolution of life on Earth. Higher fungi are almost unique in their ability to decay the chemical components of timber. Without the wood-rotting fungi we would be up to our eyes in dead trees! Fungi give us the opportunity of treating plant diseases and killing specific weeds, as well as being very useful for cleaning up polluted environments and for producing chemicals.

In short, this book will show you why it is wise to look again at fungi and appreciate these extraordinary organisms for what they are: a vital component of our lives and of the Earth’s ecosystem.

ContentsContentsContentsContentsContentsContentsContentsContents

1. Toxins - kill the primates, rule the world. Or: Don’t turn your back on a fungus!
2. Blights, rusts, bunts and mycoses.
3. Decay and degradation, a fungal speciality.
4. Joining forces - fungal co-operative ventures.
5. Fungi in medicine - antibiotics and other pharmaceuticals.
6. Turning the tables. Using fungi to control other pests.
7. Let’s party!
8. The old Kingdom in time and space.
9. Birds do it. Bees do it. Even educated fleas do it. But why?
10. The cavalry is coming. Fungi to the rescue.
Word games. Solutions to word games.

You can buy at a discount by ordering direct from the publisher at http://www.springer.de/discount/lifesci/moore.html
 

Back to top

Back to Introduction

Back to Homepage