Hektoen enteric agar: Hektoen agar is a
selective and differential agar primarily used to recover Salmonella
and Shigella from patient specimens. Hektoen contains
indicators of lactose fermentation and H2S production; as
well as inhibitors to prevent the growth of gram positive bacteria.
Oxidase: The oxidase test is used to determine
if a bacterium produces certain cytochrome c oxidases. The reagent,
tetramethyl-p-phenylenediamine is used as a redox indicator. The
reagent turns dark blue when oxidized (oxidase positive). The reagent is
colorless when reduced (oxidase-negative). Pseudomonas species
and Aeromonas species are gram-negative bacilli that are oxidase-positive.
Neisseria species are gram-negative cocci that are oxidase
positive.
Campy agar: Campylobacter CVA Agar is a selective
medium used in the primary isolation and cultivation of Campylobacter
jejuni from human fecal specimens. This selective medium contains
cefoperazone, vancomycin and amphotericin B; this combination of
antimicrobial agents inhibits the normal fecal flora for easier
detection of C. jejuni.
Oxidase: The oxidase test is used to determine
if a bacterium produces certain cytochrome c oxidases. The reagent,
tetramethyl-p-phenylenediamine is used as a redox indicator. The
reagent turns dark blue when oxidized (oxidase positive). The reagent is
colorless when reduced (oxidase-negative). Pseudomonas species
and Aeromonas species are gram-negative bacilli that are oxidase-positive.
Neisseria species are gram-negative cocci that are oxidase
positive.
Hektoen enteric agar: Hektoen agar is a
selective and differential agar primarily used to recover Salmonella
and Shigella from patient specimens. Hektoen contains
indicators of lactose fermentation and H2S production; as
well as inhibitors to prevent the growth of gram positive bacteria.
MacConkey: MacConkey agar is a selective medium
that inhibits the growth of Gram-positive bacteria due to the presence
of crystal violet and bile salts. Most Gram-negative bacteria grow well
on MacConkey. MacConkey agar also contains neutral red (a pH indicator)
and lactose (a disaccharide). Lactose fermenting bacteria or Lactose +
bacteria on MacConkey will appear as bright pink colonies. Non-lactose
fermenting bacteria will be colorless (or, if they have any color, will
be their natural color rather than pink).
BAP or SBA: An abbreviation for blood agar plate
or sheep blood agar. Blood agar contains mammalian blood (usually sheep,
rabbit or horse), typically at a concentration of 5-10%. Blood agar is
an enriched media used to isolate bacteria and to detect hemolytic
activity.
Oxidase: The oxidase test is used to determine
if a bacterium produces certain cytochrome c oxidases. The reagent,
tetramethyl-p-phenylenediamine is used as a redox indicator. The
reagent turns dark blue when oxidized (oxidase positive). The reagent is
colorless when reduced (oxidase-negative). Pseudomonas species
and Aeromonas species are gram-negative bacilli that are oxidase-positive.
Neisseria species are gram-negative cocci that are oxidase
positive.