The term saprophyte refers to the type of food a living organism eats. Sapro means rotten in Greek and phyte means plant, so a saprophyte eats dead organic matter. Some bacteria, several plants, and most fungi are saprophytes. These organisms can convert the dead organic matter into forms that are easier for other organisms to metabolize, making them essential to maintaining a healthy environment. They are also sometimes called saprobes.
Saprophytes are beneficial to the environment as they break down dead plants and animals. The energy and the organic material in the dead and decaying organic material can then be converted into energy and recycled nutrients. Saprophytes are also part of a larger group of organisms called heterotrophs, which means they must get nutrients from the environment. They cannot make their own nutrients, unlike other organisms that can harvest energy from processes like photosynthesis.
Some fungi are saprophytic. They eat the dead material and turn it into carbon dioxide, nutrients that help to make more fungi and other organic molecules. The excess organic molecules produced by the saprophyte are released into the environment, and these substances enrich the soil. Some of these molecules are organic acids, which are not easily broken down and can remain in the soil for centuries.
A saprophyte can usually eat substances like cellulose and lignin from wood, which are indigestible to a lot of organisms. The molecules the fungi produce are in a form that is easier for other organisms to utilize. Generally, fungi grow as long, thin strands that push outward because covering more ground allows the cells to find more organic matter to eat. Saprophytic fungi are also used in cheese making, and some, such as Penicillium notatum, even produce antibiotics. The majority of saprophytic fungi do not cause disease in humans.
Bacteria are also separated in groups depending on where they get their nutrients. A saprophytic bacterial species plays a similar role to the fungal species in recycling nutrients. Bacteria that live in animal stomachs and break down dead organic matter there are referred to as symbiotes instead of saprophytes.
Certain plants are saprophytes. These include a few orchid species. Several plants that reproduce by sending out spores are saprophytic during one stage of their life cycles. Some saprophytic plants do not even look like plants. For example, the monotropoid subfamily can look like mushrooms, although they still have flowers.