Question
Question: What is the difference between enriched media and enrichment media?...
What is the difference between enriched media and enrichment media?
Solution
Growth medium or Culture Medium is a sterilized medium that contains substances required for the growth of microorganisms such as bacteria, protozoans, algae and fungi. The growth medium may be solid, semisolid or liquid. It usually consists of complex ingredients such as peptone, meat extract, yeast extract, inorganic salts and organic compounds. It is prepared according to the requirement for organism growth. The growth media are of different types.
Complete explanation:
| Enriched media | Enrichment media |
|---|---|
| Enriched media means they contain all the nutrients required for the growth of a wide variety of organisms. | Enrichment media is a media that allows only the growth of a particular type of microorganism. |
| They do not contain any inhibitors to inhibit the growth of other organisms. | Inhibitors are usually added to enrichment media to stop the growth of unwanted organisms. |
| They are usually in the solidified form. | They are usually in liquid form. |
| The enriched media is used to grow nutritionally exacting fastidious microorganisms. | The enrichment media inhibit the growth of unwanted commensal and contaminating bacterias. |
| The extra nutrients added to the enriched media are blood, serum, egg yolk etc | Some of the inhibitors added to enrichment media are antibiotics, dyes, chemicals, pH alteration etc. |
| Examples include blood agar, mannitol Salt Agar and chocolate agar. | Examples include Lowenstein Jensen medium, selenite F broth, tetrathionate broth, alkaline peptone water, pseudosel Agar etc. |
Note:
Other types of media include selective media, differential media, indicator media, transport media and anaerobic media. All these media are prepared from one basal media which is known as general purpose media. They are the simplest media which supports the growth of most non-fastidious bacteria. Nutrient broth, nutrient agar and peptone water are considered as basal mediums. Basal media are generally used for the primary isolation of microorganisms.