| Culture Media Examples | Components/Comments | Primary Purpose |
|---|---|---|
| Bile esculin agar (BEA) | Nutrient agar base with ferric citrate. Hydrolysis of esculin by group D streptococci imparts a brown color to medium; sodium deoxycholate inhibits many bacteria. | Differential isolation and presumptive identification of group D streptococci and enterococci |
| Bile esculin azide agar with vancomycin | 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 | Selective and differential for cultivation of vancomycin resistant enterococci from clinical and surveillance specimens |
| Blood agar (BA) | Trypticase soy agar, Brucella agar, or beef heart infusion with 5% sheep blood | Cultivation of nonfastidious microorganisms, determination of hemolytic reactions |
| Bordet-Gengou agar | Potato-glycerol–based medium enriched with 15%- 20% defibrinated blood; contaminants inhibited by methicillin (final concentration of 2.5 µm/mL) | Isolation of Bordetella pertussis and Bordetella parapertussis |
| Brain-heart infusion agar or broth | Dextrose, pork brain, and heart dehydrated infusions | Cultivation of fastidious organisms |
| Buffered charcoal–yeast extract agar (BCYE) | Yeast extract, agar, charcoal, and salts supplemented with L-cysteine HCl, ferric pyrophosphate, ACES buffer, and alpha-ketoglutarate | Enrichment for Legionella spp. Supports the growth of Francisella and Nocardia spp. |
| Buffered charcoal yeast extract (BCYE) agar with antibiotics | BCYE supplemented with polymyxin B, vancomycin, and ansamycin to inhibit gram negative bacteria, gram-positive bacteria, and yeast, respectively | Enrichment and selection for Legionella spp. |
| Burkholderia cepacia selective agar | Bile salts, gentamicin, ticarcillin, polymyxin B, peptone, yeast extract | For recovery of B. cepacia from cystic fibrosis patients |
| Campy-blood 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 | Selective for Campylobacter spp. |
| Campylobacter thioglycollate broth | Thioglycollate broth supplemented with increased agar concentration and antibiotics | Selective holding medium for recovery of Campylobacter spp. Incubated at 4°C for cold-enrichment |
| CDC* anaerobe 5% sheep blood agar | Tryptic soy broth with phenyl-ethyl alcohol, 5% sheep blood, and added nutrients | Improved growth of obligate, slowgrowing anaerobes |
| Cefoperazone, vancomycin, amphotericin (CVA) medium | Blood-supplemented enrichment medium containing cefoperazone, vancomycin, and amphotericin to inhibit growth of most gram negative bacteria, gram-positive bacteria, and yeast, respectively | Selective medium for isolation of Campylobacter spp. |
| Cefsulodin irgasannovobiocin (CIN) agar | Peptone base with yeast extract, mannitol, and bile salts; supplemented with cefsulodin, irgasan, and novobiocin; neutral red and crystal violet indicators | Selective for Yersinia spp.; may be useful for isolation of Aeromonas spp. |
| Chocolate agar | Peptone base, enriched with solution of 2% hemoglobin or IsoVitaleX (BD BBLTM Becton Dickenson, Sparks MD) | Cultivation of fastidious microorganisms such as Haemophilus spp., Brucella spp. and pathogenic Neisseria spp. |
| Chromogenic media | Organism-specific nutrient base, selective supplements, and chromogenic substrate | Designed to optimize growth and differentiate a specific type of organism; routinely used in the identification of yeasts, methicillin-resistant Staphylococcus aureus (MRSA), and a variety of other organisms |
| Columbia colistinnalidixic acid (CNA) agar | Columbia agar base with 10 mg colistin per liter, 15 mg nalidixic acid per liter, and 5% sheep blood | Selective isolation of gram positive cocci |
| Cystine-tellurite blood agar | Infusion agar base with 5% sheep blood; reduction of potassium tellurite by Corynebacterium diphtheriae produces black colonies | Isolation of Corynebacterium diphtheriae |
| Eosin methylene blue (EMB) agar (Levine) | Peptone base containing lactose; eosin Y and methylene blue as indicators Isolation and differentiation of lactose fermenting and non lactose fermenting enteric bacilli Gram-negative broth (GN) Peptone-base broth with glucose and mannitol; sodium citrate and sodium deoxycholate act as inhibitory agents | Selective (enrichment) liquid medium for enteric pathogens |
| Hektoen enteric (HE) agar | Peptone-base agar with bile salts, lactose, sucrose, salicin, and ferric ammonium citrate; indicators include bromthymol blue and acid fuchsin | Differential, selective medium for the isolation and differentiation of Salmonella and Shigella spp. from other gram-negative enteric bacilli |
| Loeffler medium | Animal tissue (heart muscle), dextrose, egg-and-beef serum, and sodium chloride | Isolation and growth of Corynebacterium spp. |
| MacConkey agar | Peptone base with lactose; gram-positive organisms inhibited by crystal violet and bile salts; neutral red as indicator | Isolation and differentiation of lactose fermenting and non lactose fermenting enteric bacilli |
| MacConkey sorbitol agar | A modification of MacConkey agar in which lactose has been replaced with D sorbitol as the primary carbohydrate | For the selection and differentiation of E. coli O157:H7 in stool specimens |
| Mannitol salt agar | Peptone base, mannitol, and phenol red indicator; salt concentration of 7.5% inhibits most bacteria | Selective differentiation of staphylococci |
| New York City (NYC) 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) | Selective for Neisseria gonorrhoeae; also supports the growth of Ureaplasma urealyticum and some Mycoplasma spp. |
| Phenylethyl alcohol (PEA) agar | Nutrient agar base; phenylethyl alcohol inhibits growth of gram-negative organisms | Selective isolation of aerobic gram positive cocci and bacilli and anaerobic gram-positive cocci and gram-negative bacilli |
| Regan Lowe | Charcoal agar supplemented with horse blood, cephalexin, and amphotericin B | Enrichment and selective medium for isolation of Bordetella pertussis |
| Salmonella-Shigella (SS) agar | Peptone base with lactose, ferric citrate, and sodium citrate; neutral red as indicator; inhibition of coliforms by brilliant green and bile salts | Selective for Salmonella and some Shigella spp. |
| Schaedler agar | Peptone and soy protein base agar with yeast extract, dextrose, and buffers; addition of hemin, L-cysteine, and 5% blood enriches for anaerobes | Nonselective medium for the recovery of anaerobes and aerobes Selective for Campylobacter spp. and Helicobacter spp. |
| Selenite broth | Peptone-base broth; sodium selenite toxic for most Enterobacteriaceae | Enrichment of isolation of Salmonella spp. |
| Skirrow agar | Peptone and soy protein–base agar with lysed horse blood; vancomycin inhibits gram positive organisms; polymyxin B and trimethoprim inhibit most gram-negative organisms | Selective for Campylobacter spp. |
| Streptococcal selective agar (SSA) | Contains crystal violet, colistin, and trimethoprimsulfamethoxazole in 5% sheep blood agar base | Selective for Streptococcus pyogenes and Streptococcus agalactiae |
| Tetrathionate broth | Peptone-base broth; iodine and potassium iodide, bile salts, and sodium thiosulfate inhibit grampositive organisms and Enterobacteriaceae | Selective for Salmonella and Shigella spp., except Salmonella enterica Typhi |
| Thayer-Martin agar (TM) (modified Thayer Martin [MTM]) | Blood agar base enriched with hemoglobin and supplement B; contaminating organisms inhibited by colistin, nystatin, vancomycin, and trimethoprim | Selective for N. gonorrhoeae and N. meningitidis. Supports the growth of Francisella and Brucella spp. |
| Thioglycollate broth | 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 | Supports growth of anaerobes, aerobes, microaerophilic, and fastidious microorganisms |
| Xylose lysine deoxycholate (XLD) agar | Yeast extract agar with lysine, xylose, lactose, sucrose, and ferric ammonium citrate; sodium deoxycholate inhibits gram-positive organisms; phenol red as indicator | Isolation and differentiation of Salmonella and Shigella spp. from other gramnegative enteric bacilli |
| Todd-Hewitt broth supplemented with antibiotics (LIM) | Supplemented with nalidixic acid and gentamicin or colistin for greater selectivity; thioglycollate and agar reduce redox potential | Selection and enrichment for Streptococcus agalactiae in female genital specimens |
| Thiosulfate citrate bile salts (TCBS) agar | Peptone base agar with yeast extract, bile salts, citrate, sucrose, ferric citrate, and sodium thiosulfate; bromthymol blue acts as indicator | Selective and differential for Vibrio spp. |
| Trypticase soy broth (TSB) | All-purpose enrichment broth that can support the growth of many fastidious and nonfastidious bacteria | Enrichment broth used for subculturing various bacteria from primary agar plates |
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