BACTERIA MEDIA

1. Differential Media

1.1. Example

1.1.1. TCBS

1.1.1.1. contains sucrose and bromothymol blue

1.1.1.2. differentiates sucrose and non-sucrose fermenting Vibrias

1.1.2. Mannitol Salt Agar

1.1.3. ORSAB (Oxacillin Resistant Screening Agar)

1.2. Function - To distinguish one microorganism type from another growing on the same media.

2. Selective Media

2.1. Example

2.1.1. MacConkey Agar

2.1.1.1. Selects Gram negative bacteria

2.1.1.2. Contains crystal violet- inhibits the growth of Gram positive bacteria

2.1.2. XLD Agar

2.1.2.1. Selects Salmonella and Shigella

2.1.2.2. Contains bile salts that inhibits many fecal commensals

2.2. Function- To suppress or inhibit the growth of unwanted organisms, therefore giving an advantage to desired organism.

3. Maintenance Media

3.1. Example

3.1.1. Dorsal egg medium

3.1.2. Cooked meat medium

3.1.2.1. maintenance media for anaerobic bacteria

3.2. Function- Used for long storage of organisms in viable stage.

4. Enriched Media

4.1. Example

4.1.1. Blood agar

4.2. Function- To support and improve the growth of the more fastidious organisms.

5. Basal / Basic Media

5.1. Example

5.1.1. Nutrient broth

5.1.2. Agar

5.2. Function - To support the growth of microorganisms that do not have special nutritional requirements.

6. Enrichment Media

6.1. Example

6.1.1. Rappaport broth

6.1.2. Selenite broth

6.2. Function - To increase the numbers of selected organisms where they may be outnumbered by many unwanted species.

7. Transport Media

7.1. Example

7.1.1. Amies Transport Medium

7.1.2. Cary-Blair Medium

7.2. Function- To prevent overgrowth of commensals and ensure survival of aerobic and anaerobic pathogens.