Culture media are solid or liquid substances containing nutrients for cultivating (growing) of microorganisms, as well as animal cells or plant tissues. A culture is a collection of microbial cells growing on the medium (or in the medium).
Culture media are classified.
1) By source components:
- natural media - prepared from products of animal and vegetable origin (meat, ascites, bone meal, fodder yeast, blood clots, etc.)
- synthetic media - prepared from certain chemically pure organic and inorganic compounds taken in precisely specified concentrations and dissolved in double-distilled water.
2) By the degree of readiness:
- prepared nutrient media (in Petri dishes, in bottles)
- dry mixes
3) By consistency (density):
- liquid (broth)
- semi-liquid
- dense
Dense and semi-liquid media are different from liquid by the presence of a gelling agent (agar-agar, less often - gelatin). In addition, coagulated egg or whey proteins, potatoes, and silica gel media are used as dense media. Some microorganisms use gelatin as a nutrient - when they grow, the medium is dissolved.
4) Composition:
- simple: meat-infusion broth (MIB), meat-infusion agar (MIA), nutritive gelatin,
- complex - multicomponent media, which may contain amino acids, vitamins, microelements and other substances.
5) For the purpose intended:
- basic - used to cultivate most microorganisms, for example, MIB, MIA, broth, chocolate agar, peptone water.
- special - used for the isolation and cultivation of microorganisms that do not grow on simple media.
- elective (selective) - they serve to isolate a certain type of microbes, the growth of which they favor, retarding or inhibiting the growth of associated microorganisms. Media become elective when adding certain antibiotics, salts, pH changes to them. Liquid elective media are called accumulation media.
- differential - diagnostic - allow to distinguish one type of microbes from another by enzymatic activity.
- transport - designed for primary seeding and transportation of the material under study.
PK Vitanova offers a variety of cultural media produced by PanEco, Russia, and Lonza, the EU.