Termitomyces is the world’s largest edible fungus, with mushrooms that can reach up to a meter in diameter. Its protein content is on the higher end among edible mushrooms and higher than chicken. In addition, it is rich in all nine essential amino acids, and the amino acid composition of the mushroom is superior on the same level as that of meat products and that of vegetable proteins. The catch, as the name suggests, is that it takes termites to grow.
Mushroom farming termites belong to the subfamily Macrotermitinae and live in tropical Africa and Southeast Asia.
Termitomyces fungi live in a symbiotic relationship with their termite hosts. In short, termites collect and then eat dead plant materials such as leaves, wood, and grass, which pass through their intestines in a semi-digested state before being excreted into the termite nest.
There the termites cultivate their mushroom farms in specially designed chambers with carefully regulated temperature and humidity. When the termites spread their droppings over the fungus, plant matter is broken down, allowing the fungus to grow. Eventually, the termites consume the fungus as their sole food source.
But these fungi don’t just feed on termites. Once a year they sprout monstrous mushrooms that are collected and sold as an expensive delicacy in Chinese markets and in rural areas of Southeast Asia and Africa, where they are an important food source.
“In general, mushrooms are a good source of protein – and we need sustainable protein alternatives to meat,” said Professor Michael Poulsen from the University of Copenhagen’s Department of Biology. “Today, however, there are relatively few types of edible mushrooms on the market – with those grown primarily for their ease of cultivation, not for their nutritional and health value. Here we have a mushroom that is already naturally recognized as an ideal food source for animals has been optimized, so is also high in qualities as a human food source.”
Poulsen and a group of research colleagues will now set out to figure out what it takes to get Termitomyces fungi into production as a human food source, that is, without termite intervention. For this, Professor Poulsen has just received a grant from the Independent Research Fund Denmark.
“These mushrooms contain more protein than chicken and plants like soy, corn and peas, have a better amino acid composition and also contain a wide range of healthy vitamins. Nutritionally, they’re on the high end – and they even taste good. But since they cannot currently be cultivated without termite hosts, their availability as a human food source is limited
Restore conditions to termite nests
The research project will go two ways. “Right now we can grow mushroom mycelium on a small scale, but without mushrooms. We’ll see if we can ramp up production enough to make it profitable. The idea is to cultivate the mushrooms on leftover plant substrates. In Denmark, that could be wood shavings or straw that would otherwise be burned. Here we may be able to convert some of this material into fungal biomass for human or agricultural consumption,” Poulsen explained.
At the same time, the researchers will investigate what is required to promote fungal growth. “The other avenue we’re going to take is to understand the natural processes involved in the emergence of these fungi. We will try to replicate the same conditions that exist in a termite colony – in terms of temperature, humidity, CO2, plant biomass composition, etc. At the same time, we will investigate which genes are expressed in the fungi when producing fungi. If we better understand their biology, we will be better equipped to mimic the conditions fungi need in the laboratory,” Poulsen said.
Professor Poulsen claimed that the production of Termitomyces fungi primarily would have high market value as an alternative source of protein. Additionally, large-scale production could have a positive impact on local economies in parts of the world where these fungi already grow naturally but their collection is limited to termite colonies.