Fungus insect symbioses Fungi can also associate with insect species. Some species of ants culture specific fungi on plant remains they bring to their nests. The ants can then browse on the fungal mycelium that develop on the chewed leaves. Termites have symbiotic fungi within their guts, which, in association with a consortium of other microbes, help the termite digest its woody gut contents. The processes that fungi perform with their degradative enzymes are essential to the terrestrial biosphere.
Fungi are the main agents of decay of cellulose wastes produced by plants.
They decompose this material to carbon dioxide, water and fungal biomass. The same extracellular enzymes that are important in the saprophytic colonization of substrates in the biosphere can cause significant economic losses when they utilize paper, cloth, leather and hydrocarbons as substrates. They can also can cause degradative change in other materials because of their ability to produce acid as they grow, for instance glass and metal can be etched by extracellular acid production. However, fungal enzymes can be used on other, man-made substrates to provide biological cleanup. Such activity is termed bioremediation, and land contaminated with a number of hydrocarbons, and other toxic materials like PCBs can be actively bioremediated by the addition of fungi.