agar

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Related to chocolate agar: MacConkey agar

agar

(ä`gär, ā`–, ăg`är), product obtained from several species of red algae, or seaweedseaweed,
name commonly used for the multicellular marine algae. Simpler forms, consisting of one cell (e.g., the diatom) or of a few cells, are not generally called seaweeds; these tiny plants help to make up plankton.
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, chiefly from the Ceylon, or Jaffna, moss (Gracilaria lichenoides) and species of Gelidium, harvested in eastern Asia and California. Chemically, agar is a polymer made up of subunits of the sugar galactose; it is a component of the algae's cell walls. Dissolved in boiling water and cooled, agar becomes gelatinous; its chief uses are as a culture medium (particularly for bacteria) and as a laxative, but it serves also as a thickening for soups and sauces, in jellies and ice cream, in cosmetics, for clarifying beverages, and for sizing fabrics. See also RhodophytaRhodophyta
, phylum (division) of the kingdom Protista consisting of the photosynthetic organisms commonly known as red algae. Most of the world's seaweeds belong to this group.
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Agar

(ā`gər), the same as HagarHagar
or Agar
, according to the Book of Genesis, servant of Abraham's wife Sarah and mother of his eldest son, Ishmael. She and her son were sent out into the wilderness because of Sarah's jealousy. An angel aided her there.
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Agar

A major constituent of the cell walls of certain red algae, especially members of the families Gelidiaceae and Gracilariaceae. Extracted for its gelling properties, it is one of three algal polysaccharides of major economic importance, the others being alginate and carrageenan. Agar is composed of two similar fractions, agarose and agaropectin, in which the basic unit is galactose, linked alternately α-1,3-( d -galactose) and β-1,4-(α- l -galactose).

Agar is prepared by boiling the algae in water, after which the filtered solution is cooled, purified, and dried. It is an amorphous, translucent material that is packaged in granules, flakes, bricks, or sheets. One of its chief uses is as a gelling agent in media for culturing microorganisms. It is also used in making confections, as an emulsifier in cosmetics and food products, as a sizing agent, as an inert carrier of drugs in medicine, and as a laxative. See Culture

agar

[′äg·ər]
(materials)
A gelatinous product extracted from certain red algae and used chiefly as a gelling agent in culture media.

agar

a complex gelatinous carbohydrate obtained from seaweeds, esp those of the genus Gelidium, used as a culture medium for bacteria, a laxative, in food such as ice cream as a thickening agent (E406), etc.
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
Slide agglutination of growth from chocolate agar showed strong agglutination with high titre brucella antiserum stored in our laboratory.
Methods: Chocolate agar with and without supplementation of IVX was prepared.
The organism produced yellowish-brown mucoid colonies on sheep blood agar and chocolate agar after 18 hours of incubation at 35[degrees]C under CO2 atmosphere.
In the case of a gram-negative microorganism that grows only on chocolate agar, the laboratory should have a policy to check for the ability of the organism to grow on a blood agar plate if "dots" of staphylococci are placed on the agar after inoculation.
No organisms grew after a 48-h incubation at 36[degrees]C in the following culture media: blood agar in ambient air, MacConkey agar in ambient air, and chocolate agar in 5% C[O.
Histologic results were nonspecific; culture on sheep's blood Columbia agar and chocolate agar produced small colonies of gram-negative bacilli after 24 hours' incubation at 35[degrees]C in an atmosphere of 5% C[O.
CSF specimens were cultured on blood agar and chocolate agar supplemented with PolyViteX (bioMerieux, Marcy-l'Etoile, France) and incubated at 37?
All BACTEC (Becton Dickinson, Sparks, MD, USA)--positive blood culture samples were placed on 5% sheep blood agar, chocolate agar, and MacConkey agar obtained from Hy-Laboratories Ltd.
Gallbladder cultures on standard media (Columbia agar with 5% sheep's blood, chocolate agar, Brucella blood agar, and brain-heart infusion broth) were discarded when they remained sterile after 5 days of incubation.