However, a fungus can have hyphae in anaerobic environments if some of the organism is in an aerobic environment. Fungi can also survive and grow in environments with a high osmotic pressure that would kill or inhibit other microorganisms if the hyphae live partly in and partly outside of areas of high osmotic potential. Using the same mechanism, they can live and grow in fuels such as gasoline, kerosene, and diesel. The growth of fungi in aviation fuel is quite dangerous because the mycelium can block filters and tubing, preventing the flow of fuel to the engines. They can also foul hydraulic lines.
Fungi often decompose compounds that are very low in nutrients such as nitrogen and phosphorus.
Cellulose, cellophane, starches, pectin, fats, chitin, and keratin are examples of complex, low nitrogen compounds commonly attacked by fungi. Lignin, which is very resistant to decomposition, is also attacked by fungi. In remediating contaminated soil, the importance of fungi is often overlooked. These versatile microorganisms can benefit the remediation effort by breaking down complex organic molecules and compounds. Not only can hyphae penetrate inhospitable environments, and thereby carry out the decomposition of compounds found in these conditions, but they also benefit the remediation effort by improving physical conditions such as air and water movement.