Medium in microbiology refers to a mixed nutrient product artificially prepared by a method for the cultivation, isolation, identification, research, and preservation of microorganisms. The growth and reproduction of microorganisms require certain nutrients and suitable environmental conditions. In the process of developing production and disease prevention and control, humans select natural or purified nutrients, suitable osmotic pressure, acidity and alkalinity, etc. after processing, to make various nutrient substrates with different nutritional requirements, in order to cultivate and use microorganisms under artificial conditions. These are various nutrient preparations used for the artificial cultivation of microorganisms (bacteria, fungi, viruses, etc.) with different purposes such as growth, reproduction, isolation, and identification.
In the process of artificial cultivation, microorganisms must obtain nitrogen sources, carbon sources, vitamins, inorganic salts, trace elements, and various necessary growth factors from media in microbiology. Therefore, culture media are extremely important material bases for the cultivation characteristics, morphological features, physiological and biochemical, nutritional metabolism, species identification, and genetic variation of microorganisms.
With the continuous development of biological science, culture media, including natural and synthetic culture medium, have received increasing attention, and culturing has become an important discipline of biological science. In particular, media in microbiology have played an important role in industrial and agricultural production, medical and health research, and practice.
In recent years, extensive research, development, manufacturing, and application work has been done on culture media, and the functions of culture media have been gradually improved. With the application of various antibacterial drugs and biochemical reagents in culture media, the practical effect of culture media has been greatly improved, which has effectively promoted the comprehensive development of various disciplines in the field of microbiology.
Different types of microorganisms require different culture medium components and preparation methods. In practical work, different types of culture medium in microbiology suitable for different nutritional requirements and different purposes of microorganisms should be selected in order to achieve the expected results. Therefore, the quality and applicability of culture media have a direct impact on the cultivation effect of microorganisms. The purpose of studying media in microbiology is to screen and select the most suitable materials and optimal dosage through experiments, in order to achieve the best results with the lowest input.
In the field of industrial microbiology, various fermentation processes use culture media that have undergone detailed research in advance and are then put into large-scale production to reduce production costs and improve economic efficiency. Culture media used in the production of biological products such as vaccines, toxins, and toxoids have special quality requirements, and some culture media must be purified before use, otherwise bacteria may not produce toxins or may undergo mutation. In medical and health inspections, antibacterial agents, indicator agents, coagulants, etc. are often added to facilitate the growth and presentation of target bacteria and inhibit the growth of miscellaneous bacteria, in order to facilitate the separation and identification of target bacteria; some microorganisms need to be grown in living tissue cells, so various tissue cell culture media are also needed.