Microbiology Tests and Media

Flashcards covering key microbiological tests and media used in laboratory identification of bacteria.

Oxidase Test

A test used for differentiating between groups of gram-negative bacteria based on the presence of cytochrome oxidase enzyme.

Indole Test

A test that determines the capability of an organism to produce indole from tryptophan by using Kovac’s reagent.

Catalase Test

A test that detects the presence of the catalase enzyme in bacteria by the production of bubbles when exposed to hydrogen peroxide.

Bile Solubility

A test that determines the lysis of Streptococcus pneumoniae in the presence of bile salts.

Sheep Blood Agar (SBA)

A growth medium that determines hemolysis and supports the growth of most medically significant bacteria.

Chocolate Agar

An enriched medium that supports the growth of Haemophilus species and Neisseria gonorrhoeae.

Hektoen Enteric Agar (HE)

A selective medium for the isolation of Salmonella and Shigella that differentiates based on acid and H2S production.

Triple Sugar Iron Agar (TSI)

A medium used for the identification of gram-negative bacilli based on carbohydrate fermentation and H2S production.

MacConkey Agar

A selective and differential medium for the recovery of Enterobacteriaceae based on lactose fermentation.

Phenylalanine Deaminase Test

A test that detects the deamination of phenylalanine to phenyl pyruvic acid, indicated by a green color change.

Bile Esculin Test

A differential medium for isolating and identifying group D streptococci by hydrolysis of esculin into esculetin.

Voges-Proskauer Test

A test used to detect acetoin produced from glucose fermentation, indicated by a red color with reagents.

Methyl Red Test

A test for acid production from glucose, indicated by a stable red color when methyl red is added to the medium.

Citrate Test

A test for an organism's ability to utilize citrate as the sole carbon source, indicated by a color change in the medium.

Oxidase Test

A test used for differentiating between groups of gram-negative bacteria based on the presence of cytochrome oxidase enzyme.

Indole Test

A test that determines the capability of an organism to produce indole from tryptophan by using Kovac’s reagent.

Catalase Test

A test that detects the presence of the catalase enzyme in bacteria by the production of bubbles when exposed to hydrogen peroxide.

Bile Solubility

A test that determines the lysis of Streptococcus pneumoniae in the presence of bile salts.

Sheep Blood Agar (SBA)

A growth medium that determines hemolysis and supports the growth of most medically significant bacteria