With the continuous development of science and technology, we have conducted more and more research on microorganisms. Only by continuing research can we discover more information about microorganisms. The media in microbiology is an essential part of the development of microbial research. So, what are the main components of medium in microbiology? We will give you a detailed introduction below:
All nutrients that microorganisms use as a source of nitrogen in cell material or metabolic products are collectively referred to as nitrogen sources. Nitrogen sources are divided into inorganic nitrogen sources and organic nitrogen sources. Examples of organic nitrogen sources include peanut cake powder, soybean cake powder, cottonseed cake powder, wheat bran hydrolysate, corn mash, waste mycelium hydrolysate, hair hydrolysate, syrup, urea, peptone, fish meal, and beef paste. Examples of inorganic nitrogen sources include ammonia water, ammonium salt (ammonium sulfate, ammonium chloride), and ammonium nitrate. It is a critical component of various types of culture media in microbiology.
All nutrients that can be used by microorganisms as a source of carbon in cell structures and metabolic products are collectively referred to as carbon sources. Common carbon sources include sugars, starches, syrups, cellulose, alcohols, organic acids, and fats. In industrial production, the process of hydrolyzing starch into glucose is called starch saccharification, and the resulting solution is called hydrolyzed starch sugar. Its main sugar component is glucose, with varying amounts of maltose, other disaccharides, and oligosaccharides depending on the hydrolysis conditions.
Inorganic salts are the main components of media, including agar based medium. Microorganisms have two types of demand for inorganic elements, namely main inorganic elements and trace inorganic elements. Phosphorus, sulfur, potassium, sodium, magnesium, and iron can be met by adding potassium dihydrogen phosphate and magnesium sulfate. Other elements do not need to be added and can be supplemented by carbon and nitrogen sources.
In the growth and reproduction of microorganisms and synthesis of their products in industrial fermentation, inorganic salts and trace elements such as phosphorus, sulfur, iron, manganese, calcium, and magnesium are needed. Many metal ions have physiological activity on microorganisms, which is related to their concentration. Low concentrations often have a stimulating effect, while high concentrations have an inhibitory effect.
Growth factors are a class of organic compounds that are necessary for regulating the normal growth and metabolism of microorganisms, but cannot be synthesized by simple sources of carbon and nitrogen. In addition to vitamins, general growth factors also include bases, purines, pyrimidines, biotin, and niacin, and sometimes include the amino acids needed by mutant strains with amino acid nutritional defects.