In: Biology
Microorganisms are grown in culture media/growth media containing all the essential nutrients for their optimal growth, it can be solid/liquid/semi-solid in nature and are used for the general cultivation and maintenance of bacteria kept in laboratory culture collections.
Definition : Pure culture thus can be defined as the population of cells which are genetically identical, derived from a single type of cells i.e. if the growth media contains only one type of bacterial species like E.coli then it is known as pure culture. They are prepared to isolate the specific microorganism and study its metabolic characteristics.
Thus the cells in pure culture culture are genetic clones of each other.
Considering an example : If we collect a soil sample and incubate it in specific type of broth which allows only the growth of medium specific bacterial species for a specific characteristic, we will be able to select a few from a large number of bacterial species and for these few bacterial species we make pure culture to test each bacterial species seperately for their specific metabolic and physiological characterics.
They are isolated through a number of aseptic techniques like spread plate, streak plate and pour plate method to avoid the risk of contamination.