What is the difference between enriched media and enrichment media?
Enriched media selects for a certain group of microbes while an enrichment media selects for one microbe.
Enriched media contain the nutrients required to support the growth of a wide variety of organisms, including some fastidious ones.
They are commonly used to grow as many different types of microbes as are present in the specimen.
Examples are:
Blood agar is an enriched medium in which nutritionally-rich whole blood supplements the basic nutrients.
and
Chocolate agar is enriched with heat-treated blood (40-45°C), which turns brown and gives the medium that chocolate color.
Enrichment media promotes the growth of a particular organism by providing it with the essential nutrients and rarely contains certain inhibitory substance to prevent the growth of normal competitors.
An example is:
Selenite F broth favors the growth of Salmonella also prevents
the growth of normal competitors like E. coli. E.coli does not die in the medium but they do not flourish like Salmonella does.
If we couldn’t separate out microbes, we would have only this:
