Plating Media for Routine Bacteriology (Components) Flashcards
Nutrient agar base with ferric citrate. Hydrolysis of
esculin by group D streptococci imparts a brown
color to medium; sodium deoxycholate inhibits
many bacteria.
Bile esculin agar (BEA)
Contains azide to inhibit gram-negative bacteria,
vancomycin to select for resistant gram-positive
bacteria, and bile esculin to differentiate enterococci
from other vancomycin-resistant bacteria
that may grow
Bile esculin azide agar with vancomycin
Trypticase soy agar, Brucella agar, or beef heart
infusion with 5% sheep blood
Blood agar (BA)
Potato-glycerol–based medium enriched with 15%-
20% defibrinated blood; contaminants inhibited by
methicillin (final concentration of 2.5 μm/mL)
Bordet-Gengou agar
Dextrose, pork brain, and heart dehydrated infusions
Brain-heart infusion agar or broth
Yeast extract, agar, charcoal, and salts supplemented
with L-cysteine HCl, ferric pyrophosphate, ACES
buffer, and alpha-ketoglutarate
Buffered charcoal–yeast extract agar (BCYE)
BCYE supplemented with polymyxin B, vancomycin,
and ansamycin to inhibit gram-negative bacteria,
gram-positive bacteria, and yeast, respectively
Buffered charcoal–yeast extract (BCYE) agar with antibiotics
Bile salts, gentamicin, ticarcillin, polymyxin B,
peptone, yeast extract
Burkholderia cepacia selective agar
Contains vancomycin (10 mg/L), trimethoprim
(5 mg/L), polymyxin B (2500 U/L), amphotericin B
(2 mg/L), and cephalothin (15 mg/L) in a Brucella
agar base with sheep blood
Campy-blood agar
Thioglycollate broth supplemented with increased
agar concentration and antibiotics
Campylobacter thioglycollate broth
Tryptic soy broth with phenyl-ethyl alcohol, 5% sheep
blood, and added nutrients
CDC* anaerobe 5% sheep blood agar
Blood-supplemented enrichment medium containing
cefoperazone, vancomycin, and amphotericin to
inhibit growth of most gram-negative bacteria,
gram-positive bacteria, and yeast, respectively
Cefoperazone, vancomycin, amphotericin (CVA) medium
Peptone base with yeast extract, mannitol, and bile
salts; supplemented with cefsulodin, irgasan, and
novobiocin; neutral red and crystal violet indicators
Cefsulodin-irgasan-novobiocin (CIN) agar
Peptone base, enriched with solution of 2% hemoglobin
or IsoVitaleX (BD BBLTM Becton Dickenson, Sparks MD)
Chocolate agar
Organism-specific nutrient base, selective supplements,
and chromogenic substrate
Chromogenic media
Columbia agar base with 10 mg colistin per liter,
15 mg nalidixic acid per liter, and 5% sheep
blood
Columbia colistin-nalidixic acid (CNA) agar
Infusion agar base with 5% sheep blood; reduction of
potassium tellurite by Corynebacterium diphtheriae
produces black colonies
Cystine-tellurite blood agar
Peptone base containing lactose; eosin Y and
methylene blue as indicators
Eosin methylene blue (EMB) agar (Levine)
Peptone-base broth with glucose and mannitol;
sodium citrate and sodium deoxycholate act as
inhibitory agents
Gram-negative broth (GN)
Peptone-base agar with bile salts, lactose, sucrose,
salicin, and ferric ammonium citrate; indicators
include bromthymol blue and acid fuchsin
Hektoen enteric (HE) agar
Animal tissue (heart muscle), dextrose, egg-and-beef
serum, and sodium chloride
Loeffler medium
Peptone base with lactose; gram-positive organisms
inhibited by crystal violet and bile salts; neutral red
as indicator
MacConkey agar
A modification of MacConkey agar in which lactose
has been replaced with D-sorbitol as the primary
carbohydrate
MacConkey sorbitol agar
Peptone base, mannitol, and phenol red indicator;
salt concentration of 7.5% inhibits most bacteria
Mannitol salt agar
Peptone agar base with cornstarch, supplemented
with yeast dialysate, 3% hemoglobin, and horse
plasma; antibiotic supplement includes vancomycin
(2 μg/mL), colistin (5.5 μg/mL), amphotericin B
(1.2 μg/mL), and trimethoprim (3 μg/mL)
New York City (NYC) agar
Nutrient agar base; phenylethyl alcohol inhibits
growth of gram-negative organisms
Phenylethyl alcohol (PEA) agar
Charcoal agar supplemented with horse blood,
cephalexin, and amphotericin B
Regan Lowe
Peptone base with lactose, ferric citrate, and sodium
citrate; neutral red as indicator; inhibition of
coliforms by brilliant green and bile salts
Salmonella-Shigella (SS) agar
Peptone and soy protein base agar with yeast
extract, dextrose, and buffers; addition of hemin,
L-cysteine, and 5% blood enriches for anaerobes
Schaedler agar
Peptone-base broth; sodium selenite toxic for most
Enterobacteriaceae
Selenite broth
Peptone and soy protein–base agar with lysed horse
blood; vancomycin inhibits gram-positive organisms;
polymyxin B and trimethoprim inhibit most
gram-negative organisms
Skirrow agar
Contains crystal violet, colistin, and trimethoprim-sulfamethoxazole in 5% sheep blood agar base
Streptococcal selective agar (SSA)
Peptone-base broth; iodine and potassium iodide,
bile salts, and sodium thiosulfate inhibit grampositive
organisms and Enterobacteriaceae
Tetrathionate broth
Blood agar base enriched with hemoglobin and
supplement B; contaminating organisms inhibited
by colistin, nystatin, vancomycin, and trimethoprim
Thayer-Martin agar (TM)
(modified Thayer Martin [MTM])
Pancreatic digest of casein, soy broth, and glucose
enrich growth of most microorganisms; includes
reducing agents thioglycollate, cystine, and
sodium sulfite; semisolid medium with a low
concentration of agar reducing oxygen diffusion
in the medium
Thioglycollate broth
Peptone base agar with yeast extract, bile salts,
citrate, sucrose, ferric citrate, and sodium
thiosulfate; bromthymol blue acts as indicator
Thiosulfate citrate–bile salts (TCBS) agar
Supplemented with nalidixic acid and gentamicin or
colistin for greater selectivity; thioglycollate and
agar reduce redox potential
Todd-Hewitt broth supplemented with antibiotics (LIM)
All-purpose enrichment broth that can support the
growth of many fastidious and nonfastidious
bacteria
Trypticase soy broth (TSB)
Yeast extract agar with lysine, xylose, lactose,
sucrose, and ferric ammonium citrate; sodium
deoxycholate inhibits gram-positive organisms;
phenol red as indicator
Xylose lysine deoxycholate (XLD) agar
