Classification of Culture Media and their uses
Classification |
Types of Culture Media |
Purpose |
General Purpose Media |
Nutrient Agar |
Supports the growth of a
wide range of microorganisms and used as a general-purpose medium for
cultivating bacteria. |
Tryptic Soy Agar (TSA) |
Provides a rich source of
nutrients and supports the growth of a wide variety of microorganisms,
commonly used for bacterial isolation and enumeration. |
|
Luria-Bertani (LB) Agar |
Used for the cultivation of
bacteria, especially Escherichia coli, and other fastidious microorganisms. |
|
Brain Heart Infusion (BHI)
Agar |
Contains an infusion of calf
brains and hearts, used to support the growth of fastidious organisms such as
Streptococci and Neisseria species. |
|
Enriched Media |
Blood Agar |
Supplemented with sheep or
horse blood, used to support the growth of a wide range of microorganisms and
to detect and differentiate hemolytic bacteria. |
Chocolate Agar |
Prepared by lysing red blood
cells, provides essential growth factors for fastidious bacteria like
Haemophilus influenzae and Neisseria gonorrhoeae. |
|
Thayer-Martin Agar |
Selective medium containing
antibiotics to inhibit the growth of normal flora and facilitate the
isolation of Neisseria gonorrhoeae. |
|
Lowenstein-Jensen Medium |
Used for the isolation and
cultivation of Mycobacterium tuberculosis and other mycobacterial species. |
|
Robertson's Cooked Meat
Medium |
Utilized for the cultivation
of anaerobic bacteria, especially Clostridium species. |
|
Brucella Agar |
Designed for the cultivation
of Brucella species, commonly used in the diagnosis of brucellosis. |
|
Selective Media |
MacConkey Agar |
Selective and differential
medium used for the isolation and differentiation of lactose-fermenting and
non-fermenting gram-negative enteric bacteria. |
Mannitol Salt Agar |
Selective medium for the
isolation and differentiation of Staphylococcus species, particularly
Staphylococcus aureus. |
|
Eosin Methylene Blue (EMB)
Agar |
Selective and differential
medium for the detection and differentiation of gram-negative enteric
bacteria, such as Escherichia coli, based on their ability to ferment
lactose. |
|
Hektoen Enteric Agar |
Selective and differential
medium for the isolation and differentiation of Salmonella and Shigella
species from other enteric bacteria. |
|
Xylose Lysine Deoxycholate
(XLD) Agar |
Selective and differential
medium for the isolation and differentiation of Salmonella and Shigella
species, primarily used for the detection of enteric pathogens in clinical
specimens. |
|
Differential Media |
Blood Agar |
Differentiates bacteria
based on their hemolytic activity, allowing the identification of hemolytic
patterns such as alpha, beta, and gamma hemolysis. |
MacConkey Agar |
Differentiates
lactose-fermenting (pink colonies) and non-lactose-fermenting (colorless
colonies) gram-negative enteric bacteria. |
|
Eosin Methylene Blue (EMB)
Agar |
Distinguishes between strong
lactose fermenters (dark-centered colonies) and weak lactose fermenters/non-fermenters
(colonies with a metallic green sheen or colorless colonies). |
|
Hektoen Enteric Agar |
Allows the differentiation
of Salmonella and Shigella species based on their ability to ferment lactose
and produce hydrogen sulfide (H2S). |
|
Xylose Lysine Deoxycholate
(XLD) Agar |
Differentiates Salmonella
and Shigella species based on their ability to ferment xylose and lactose, as
well as their production of hydrogen sulfide (H2S). |
|
Transport Media |
Amies Transport Medium |
Preserves and maintains the
viability of microorganisms during transportation to the laboratory. |
Stuart Transport Medium |
Similar to Amies medium,
used for the transport of clinical specimens containing bacteria. |
|
Cary-Blair Transport Medium |
Used for the preservation
and transport of enteric pathogens, particularly those causing diarrheal
diseases. |
|
Port-A-Cul® Transport
Systems |
Contain various formulations
to preserve and transport specific microorganisms, such as Neisseria
gonorrhoeae, Bordetella pertussis, and Mycoplasma species. |
|
UTM (Universal Transport
Medium) |
Used for the collection,
transport, and preservation of various viruses, including respiratory viruses
like influenza and SARS-CoV-2. |
|
Viral Transport Medium (VTM) |
Specifically designed for
the transport and preservation of viruses, including SARS-CoV-2. |