Saprotrophic nutrition is a process of chemoheterotrophic extra-cellular digestion

Extra-cellular digestion

Extra-cellular digestion is a process where saprobionts feed by secreting enzymes through the cell membrane onto the food which is in the digestive system spaces. The enzymes catalyse the food into molecules small enough for them to be phagocytosed...

 involved in the processing of dead or decayed organic matter that occurs in saprotrophs or heterotroph

Heterotroph

A heterotroph is an organism that cannot fix carbon and uses organic carbon for growth. This contrasts with autotrophs, such as plants and algae, which can use energy from sunlight or inorganic compounds to produce organic compounds such as carbohydrates, fats, and proteins from inorganic carbon...

s, and is most often associated with fungi

Fungus

A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...

, for example Mucor

Mucor

Mucor is a microbial genus of about 3000 species of moulds commonly found in soil, digestive systems, plant surfaces, and rotten vegetable matter.-Description:...

and Rhizopus

Rhizopus

Rhizopus is a genus of common saprobic fungi on plants and specialized parasites on animals. They are found on a wide variety of organic substrates, including "mature fruits and vegetables", faeces, jellies, syrups, leather, bread, peanuts and tobacco. Some Rhizopus species are opportunistic agents...

. The process is most often facilitated through the active transport

Active transport

Active transport is the movement of a substance against its concentration gradient . In all cells, this is usually concerned with accumulating high concentrations of molecules that the cell needs, such as ions, glucose, and amino acids. If the process uses chemical energy, such as from adenosine...

 of such materials through endocytosis

Endocytosis

Endocytosis is a process by which cells absorb molecules by engulfing them. It is used by all cells of the body because most substances important to them are large polar molecules that cannot pass through the hydrophobic plasma or cell membrane...

 within the internal mycelium and its constituent hypha

Hypha

A hypha is a long, branching filamentous structure of a fungus, and also of unrelated Actinobacteria. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium; yeasts are unicellular fungi that do not grow as hyphae.-Structure:A hypha consists of one or...

e.

Explanation

As matter decomposes within a medium in which a saprotroph is residing, the saprotroph breaks such matter down into its composites.

• Protein
  Protein
  Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
  
  s are broken down into their amino acid
  Amino acid
  Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...
  
   composites through the breaking of peptide bonds by protease
  Protease
  A protease is any enzyme that conducts proteolysis, that is, begins protein catabolism by hydrolysis of the peptide bonds that link amino acids together in the polypeptide chain forming the protein....
  
  s.
• Lipid
  Lipid
  Lipids constitute a broad group of naturally occurring molecules that include fats, waxes, sterols, fat-soluble vitamins , monoglycerides, diglycerides, triglycerides, phospholipids, and others...
  
  s are broken down into fatty acid
  Fatty acid
  In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...
  
  s and glycerol
  Glycerol
  Glycerol is a simple polyol compound. It is a colorless, odorless, viscous liquid that is widely used in pharmaceutical formulations. Glycerol has three hydroxyl groups that are responsible for its solubility in water and its hygroscopic nature. The glycerol backbone is central to all lipids...
  
   by lipase
  Lipase
  A lipase is an enzyme that catalyzes the formation or cleavage of fats . Lipases are a subclass of the esterases.Lipases perform essential roles in the digestion, transport and processing of dietary lipids in most, if not all, living organisms...
  
  s.
• Starch
  Starch
  Starch or amylum is a carbohydrate consisting of a large number of glucose units joined together by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store...
  
   is broken down into simple disaccharides by amylase
  Amylase
  Amylase is an enzyme that catalyses the breakdown of starch into sugars. Amylase is present in human saliva, where it begins the chemical process of digestion. Food that contains much starch but little sugar, such as rice and potato, taste slightly sweet as they are chewed because amylase turns...
  
  s.

These products are re-absorbed into the hypha through the cell wall via endocytosis and passed on throughout the mycelium complex. This facilitates the passage of such materials throughout the organism and allows for growth and, if necessary, repair.

Conditions

In order for a saprotrophic organism to facilitate optimal growth and repair, favourable conditions and nutrients must be present. Optimal conditions refers to several conditions which optimise the growth of saprotrophic organisms, such as;

1. Presence of water: 80–90% Of the fungus is composed of water by mass, and requires excess water for absorption due to the evaporation of internally retent water.
2. Presence of oxygen: Very few saphrotrophic organisms can endure anaerobic conditions due to their growth above media such as water or soil.
3. Neutral-acidic pH: The condition of neutral or mildly acidic conditions under pH 7 are required.
4. Low-medium temperature: The majority of saprotrophic organisms require temperatures between 1 °C and 35 °C, with optimum growth occurring at 25 °C.

The majority of nutrients taken in by such organisms must be able to provide carbon, proteins, vitamins and in some cases, ion

Ion

An ion is an atom or molecule in which the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. The name was given by physicist Michael Faraday for the substances that allow a current to pass between electrodes in a...

s. Due to the carbon composition of the majority of organisms, dead and organic matter provide rich sources of polysaccharides disaccharides such as glucose

Glucose

Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...

, maltose

Maltose

Maltose , or malt sugar, is a disaccharide formed from two units of glucose joined with an αbond, formed from a condensation reaction. The isomer "isomaltose" has two glucose molecules linked through an α bond. Maltose is the second member of an important biochemical series of glucose chains....

, and starch

Starch

Starch or amylum is a carbohydrate consisting of a large number of glucose units joined together by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store...

.

In terms of nitrogen-rich sources, saprotrophs require combined protein for the creation of proteins, which is facilitated by the absorption of amino acids, and usually taken from rich soil. Although both ions and vitamins are rare, thiamine or ions such as potassium, phosphorus, and magnesium aid the growth of the mycelium.

See also

• Detritivore
  Detritivore
  Detritivores, also known as detritophages or detritus feeders or detritus eaters or saprophages, are heterotrophs that obtain nutrients by consuming detritus . By doing so, they contribute to decomposition and the nutrient cycles...
  
  
• Holozoic nutrition
  Holozoic nutrition
  Holozoic nutrition is a method of nutrition that involves the ingestion of liquid or solid organic material, digestion, absorption and assimilation of it to utilize it...
  
  
• Parasitic nutrition
  Parasitic nutrition
  Parasitic nutrition is a mode of nutrition where organism lives on the body surface or inside the body of another type of organism and obtains nutrition directly from the body of the other organism...
  
  
• Photoautotrophic nutrition
• Chemoautotrophic nutrition
• Photosynthesis
  Photosynthesis
  Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...
  
  
• Wood-decay fungus
  Wood-decay fungus
  A wood-decay fungus is a variety of fungus that digests moist wood, causing it to rot. Some wood-decay fungi attack dead wood, such as brown rot, and some, such as Armillaria , are parasitic and colonize living trees. Fungi that not only grow on wood but actually cause it to decay, are called...