Agarlevyjä

Agarlevyjä, often translated as agar plates or agar dishes, are essential tools in microbiology and biotechnology. They consist of a petri dish or a similar container filled with a sterile growth medium. This medium is typically a solidified gel, with agar being the primary solidifying agent, hence the name. Agar is a polysaccharide extracted from red algae and is favored for its ability to remain solid at incubator temperatures while being non-nutritive to most microorganisms.

The agar medium is formulated with specific nutrients, salts, and other compounds that are necessary to support the growth of particular types of bacteria, fungi, or other microbes. Before use, the agar is sterilized, usually by autoclaving, to eliminate any pre-existing contaminants. Once cooled and solidified, the surface of the agar plate can be inoculated with a sample suspected to contain microorganisms. This is often done by streaking a loop of the sample across the agar surface or by spreading a liquid sample.

After inoculation, the plates are incubated under controlled conditions of temperature, humidity, and sometimes atmospheric composition, which are optimal for the growth of the target microorganisms. Over time, if viable microbes are present in the sample, they will multiply and form visible colonies on the agar surface. Each colony typically arises from a single microbial cell or a small cluster of cells, allowing for the isolation and study of individual microbial species. Agar plates are fundamental for tasks such as microbial identification, antibiotic susceptibility testing, cell culture, and various research applications.