chocolate agar

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Related to chocolate agar: MacConkey agar

choc·o·late a·gar

blood agar heated until the blood turns brownish, used especially to isolate Haemophilus, Neisseria, and other species for which unheated blood is inhibitory.
Blood agar that has been heated to open the pyrrole ring, forming hemin, a required growth factor for bacteria lacking hemolysins. Chocolate agars are usually incubated in a microaerophilic—3–10% CO2—environment, providing ideal growth conditions for H influenzae, Neisseria spp, and fastidious anaerobes


a dried hydrophilic, colloidal substance extracted from various species of red algae. When suspended in a liquid medium and heated to 212°F (100°C), the agar dissolves. When it is allowed to cool to 110°F (43°C) the medium becomes a solid gel. It is used in culture media for bacteria and other microorganisms, in making emulsions, and as a supporting medium for immunodiffusion and immunoelectrophoresis. Because of its bulk it is also used in medicines to promote peristalsis and relieve constipation.

birdseed agar
one containing Guizotia abyssinicia (Niger) seed and creatinine, used for growing Cryptococcus neoformans. Called also Niger agar.
bismuth sulfite agar
a special preparation used for isolation of salmonellae from food.
blood agar
a culture medium used for the growth of bacteria. Consists of agar and intact erythrocytes.
brain heart infusion agar
used for cultivating the yeast phase of dimorphic fungi.
brilliant green agar
used to cultivate salmonellae.
chocolate agar
an enriched agar for the growth of Hemophilus, some Actinobacillus, and Taylorella spp. A molten agar and blood mixture is held at 122°F (50°C) prior to pouring plates. The additional nutrients supplied are hemin and NAD.
agar diffusion test
see antimicrobial sensitivity test.
eosin-methylene blue (EMB) agar
used for the identification of Eschericha coli.
agar gel immunodiffusion test
see immunodiffusion tests.
MacConkey agar
contains bile salts, lactose and neutral red indicator for isolation of enterobacteria.
mannitol salt agar
selective for staphylococci.
milk agar
contains skim milk and used to demonstrate casein digestion.
Niger seed agar
see birdseed agar (above).
nutrient agar
the basic growth medium for bacteria, composed of beef extract and peptone.
potato dextrose agar
used in cultivating fungi; promotes sporulation and pigmentation.
Sabouraud's dextrose agar
one used for isolation of fungi. See also dermatophyte test medium.
agar sausage
see medium sausage.
xylose lysine (XLD) agar
used to differentiate Enterbacteriaceae.
References in periodicals archive ?
029 * Values along the same column-for each media with different superscripts are significantly different at different storage times, NA= Nutrient agar, MCA= MacConkey agar, CHA= Chocolate agar Table 5: Characterization and identification of micro-organisms Sample NA MCA CHA Gram +ve -ve +ve Motility -ve +ve -ve Catalase +ve +ve -ve Coagulase +ve -ve -ve Indole Test -ve +ve NT Oxidase sugar -ve -ve -ve Glucose +ve +ve +ve Sucrose +ve +ve +ve Maltose +ve +ve -ve Lactose +ve +ve +ve Arabinose -ve -ve -ve Mannitose +ve +ve +ve Sorbitose -ve -ve -ve Urease +ve -ve - Staphylococcus Escherichia Enterococcusa aureus Coli Faecalis NA = Nutrient agar, MCA = MacConkey agar, CHA = Chocolate agar
5 ml) of the resuspended amoebae were spread onto chocolate agar plates and allowed to dry under a laminar flow hood for 1-2 h.
Slide agglutination of growth from chocolate agar showed strong agglutination with high titre brucella antiserum stored in our laboratory.
From this diluted well mixed sputum, 10ul was transerred in each plate of Chocolate agar, Sheep Blood Agar, and MacConkey agar (MAC).
All the sputum samples were cultured on Blood agar, Chocolate agar and MacConkey agar.
After 11 days of incubation on chocolate agar at 37[degrees]C, the lung biopsy culture grew 1 pink colony.
When growth is detected in a blood culture bottle three drops of blood were sample with a sterile syringe and were inoculated onto blood agar, chocolate agar and Macconkey agar (Hi-Media, Mumbai, India).
Cultures on blood agar, chocolate agar and EMB were incubated at 37 [degrees]C for 24 hours; cultures on SDA were incubated at 25 [degrees]C for 2 weeks.
13 7 yeasts and antifungal susceptibility testing; Thioglycollate medium USP; Antibiogram discs; Blood agar base; Blue agar AABTL; Simmons citrate agar; Columbia blood agar; Drigalski lactose agar; Desoxycholate citrate agar, modified Leifson; Desoxycholate citrate agar, modified Hynes; Eosin Methylene blue agar; Selenite broth base; Yersinia agar; Nutrient broth (single); Nutrient broth; Mannitol salt agar; Mueller Hinton agar; Agar malonate; Sabouraud Dextrose Agar; Mac Conkey agar without salt; Cary Blair agar; Triple sugar iron agar; Anse calibrated 1 microliter; Anse calibrated 10 microliters; Chocolate agar base; CLED Agar; Brilliant Green Agar; Brilliant Green solution 0.
The ear swabs, obtained from junction of horizontal and vertical canal, were incubated at 37[degrees]C on blood agar, Mac-Conkey's agar, chocolate agar and V-J agar for 24 hours under aerobic conditions.
Specimens were inoculated on blood agar with optochin disc (Oxoid, UK), incubated at 370C aerobically, Chocolate agar (Oxoid, UK) incubated in 5-10% CO2 for Haemophilus influenzae, MacConkey agar (Oxoid, UK) for Gram-negative bacilli.