1. The main function of carbon source is to participate in microbial synthesis of metabolites.
Microorganisms have a wide demand for carbon compounds. According to different carbon sources, carbon source materials can be divided into inorganic carbon source materials and organic carbon source materials. Sugar is a good carbon source, especially monosaccharide (glucose, fructose) and disaccharide (sucrose, maltose, lactose), which can be used by most microorganisms.
2. The main function of nitrogen source: the main components of protein eggs and nucleic acids of microbial cells.
Nitrogen is of great significance to the growth and development of microorganisms. Microorganisms use it to synthesize amino acids and bases in cells, and then to synthesize protein, nucleic acids, nitrogen-containing metabolites and other cellular components.
3. The main functions of inorganic salts are: to constitute the components of cells, to act as the components of enzymes, to maintain the activity of enzymes, to adjust the osmotic pressure, hydrogen ion concentration and redox potential of cells, and to act as the energy source of some autotrophic bacteria.
4. The main function of growth factors is to promote the growth of microorganisms.
5. The main function of free water: As a solvent for cells to absorb nutrients and excrete metabolites and a medium for biochemical reactions, a certain amount of water is a necessary condition for maintaining cell osmotic pressure. Because of its high specific heat and good thermal conductor, water can effectively regulate the temperature in cells.
Extended data:
By analyzing the chemical composition of microbial cells, it is found that there is no essential difference between microbial cells and other biological cells. The average water content of microbial cells is about 80%. The remaining 20% is dry matter. There are protein, nucleic acid, carbohydrate, lipid and minerals in the dry matter.
These dry substances are composed of carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur, potassium, calcium, magnesium, iron and other major chemical elements, among which carbon, hydrogen, oxygen and nitrogen are the four major elements that constitute organic matter, accounting for about 90% ~ 97% of dry substances. The remaining 3% ~ 10% are mineral elements, which also play an important role in the growth of microorganisms.
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