May 20, 2022

Microbiology (English: microbiology) is a field of biology that targets microorganisms. Microorganisms refer to organisms of microscopic size or smaller, such as (genuine) bacteria, archaea, prokaryotes, and fungi. However, when the term microbiology is used, it often targets prokaryotes (bacteria, archaea). It may also include viruses. Perform biochemical analysis (chemotherapy). Currently, as one of the geoscientific factors, we are also conducting analysis on a large scale such as microbial ecology including microorganisms.


17th-18th century-Antonie van Leeuwenhoek's microscopic observation gives rise to the concept of microorganisms. After this, microbiology will stop its course. 1837-Yeast, the organism that undergoes alcoholic fermentation by Canyar de Latour, Schwann, and Kutzing, is a microorganism, and the reaction is based on the physiological function of yeast. Around 1840-Introduction of disinfectants was promoted to prevent surgical sepsis due to surgery. 1857-Louis Pasteur announces that "all fermentation processes are based on microbial activity." Over the next 20 years, Pasteur continued to study many fermentation reactions. 1860-Louis Pasteur uses a swan neck flask to deny the spontaneous theory. Tyndall is also conducting experiments to deny the spontaneous theory with the concept of sterility. 1870-Pure culture was defined by De Barry and Brefeld as "a culture that contains only one type of microorganism." 1876-Robert Koch isolates the anthrax-causing bacterium (Bacillus anthracis) and proves its pathogenicity. 1892-Ivanovsky's experiments suggest the presence of a virus that permeates cell filters. After the 20th century-A deeper understanding of biochemistry through microbiology. In addition, genetic experiments using induction such as mutation proceeded in microorganisms, and after 1945, genetics and biochemistry began to merge with microbiology.


Pure culture

(See culture for details) The most basic experiment or method of microbiology is pure culture technique (separation) of microorganisms. In the environment, various types of microorganisms interact with each other, and in order to explore the properties of each type excluding these interactions, the technique of purely culturing microorganisms is the most basic. Become. In addition, pure culture involves not only microorganisms such as sterilization of instruments and composition of culture medium, but also basic techniques for dealing with cells. Bacteria that can be isolated differ depending on the composition, temperature, and culture time of the medium. Separation from soil In a typical method (dilution plate method), soil obtained from the environment is suspended in sterile water or the like, and after standing, the supernatant is appropriately diluted and applied to an agar medium. Store at an appropriate temperature and wait for the growth of bacteria. The grown colony is further applied to an agar medium with a platinum loop or the like to obtain a single colony (colony derived from a single cell). Extraneous dilution method It is performed when it cannot be grown on an agar medium. A culture medium derived from a single cell is obtained by diluting the medium in which the bacteria are suspended many times and culturing. Strictly speaking, the bacteria may be entangled with each other, or multiple bacteria may be attached to the garbage, so be careful.

Refractory microorganisms

Research based on pure culture has become the royal road in microbiology, but it does not require unknown factors.