growth medium

7/25/2019 Growth Medium

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An agar plateis a sterile Petri dishthat contains agrowth medium(typically agarplus nutrients) used to culturemicroorganismsor small plantslike the mossPhyscomitrella patens.

Selectivegrowth compounds may also be added to the media,such as antibiotics.

Individual microorganisms placed on the plate will grow intoindividual colonies, each a clonegenetically identical to theindividual ancestor organism (except or the low, unavoidablerate o mutation).

!hus, the plate can be used either to estimate theconcentration o organisms in a li"uid cultureor a suitabledilution o that culture, using a colony counter, or to generategenetically pure cultures rom a mixed culture o geneticallydi#erent organisms, using a techni"ue known as streaking.
http://en.wikipedia.org/wiki/Petri_dishhttp://en.wikipedia.org/wiki/Growth_mediumhttp://en.wikipedia.org/wiki/Agarhttp://en.wikipedia.org/wiki/Microbiological_culturehttp://en.wikipedia.org/wiki/Microorganismshttp://en.wikipedia.org/wiki/Planthttp://en.wikipedia.org/wiki/Mosshttp://en.wikipedia.org/wiki/Physcomitrella_patenshttp://en.wikipedia.org/wiki/Growth_mediumhttp://en.wikipedia.org/wiki/Antibiotichttp://en.wikipedia.org/wiki/Colony_(biology)http://en.wikipedia.org/wiki/Cloninghttp://en.wikipedia.org/wiki/Mutationhttp://en.wikipedia.org/wiki/Microbiological_culturehttp://en.wikipedia.org/wiki/Colony_counterhttp://en.wikipedia.org/wiki/Colony_counterhttp://en.wikipedia.org/wiki/Microbiological_culturehttp://en.wikipedia.org/wiki/Mutationhttp://en.wikipedia.org/wiki/Cloninghttp://en.wikipedia.org/wiki/Colony_(biology)http://en.wikipedia.org/wiki/Antibiotichttp://en.wikipedia.org/wiki/Growth_mediumhttp://en.wikipedia.org/wiki/Physcomitrella_patenshttp://en.wikipedia.org/wiki/Mosshttp://en.wikipedia.org/wiki/Planthttp://en.wikipedia.org/wiki/Microorganismshttp://en.wikipedia.org/wiki/Microbiological_culturehttp://en.wikipedia.org/wiki/Agarhttp://en.wikipedia.org/wiki/Growth_mediumhttp://en.wikipedia.org/wiki/Petri_dish


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In this techni"ue, a drop o the culture on theend o a thin, sterileloop o wire is $streaked$across the surace o the agar leavingorganisms behind, a higher number at thebeginning o the streak and a lower numberat the end.

At some point during a successul $streak$,the number o organisms deposited will besuch that distinct individual colonies will growin that area which may be removed orurther culturing, using another sterile loop.%&'
http://en.wikipedia.org/wiki/Sterilization_(microbiology)http://en.wikipedia.org/wiki/Streaking_(microbiology)http://en.wikipedia.org/wiki/Cylindricalhttp://en.wikipedia.org/wiki/Cylindricalhttp://en.wikipedia.org/wiki/Streaking_(microbiology)http://en.wikipedia.org/wiki/Sterilization_(microbiology)


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A Petri dishis a shallow glassor plasticcylindricallidded dish that biologistsuse to culturecells. It was named ater ermanbacteriologistulius Petri, who invented it when working as anassistant to *obert +och. lass Petri dishes can bereused by sterili-ation(or example, dry heatingin a hot air oven at &/ 01 or one hour)2 plasticPetri dishes must be disposed o ater one use.

3or microbiology, agar platesare very re"uentlyused. !he dish is partially 4lled with warm li"uidagaralong with a particular mix o nutrients, saltsand amino acidsand, optionally, antibiotics. Aterthe agar solidi4es, the dish is ready to receive amicrobeladen sample.
http://en.wikipedia.org/wiki/Glasshttp://en.wikipedia.org/wiki/Plastichttp://en.wikipedia.org/wiki/Cylindricalhttp://en.wikipedia.org/wiki/Microbiologisthttp://en.wikipedia.org/wiki/Microbiological_culturehttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Germanyhttp://en.wikipedia.org/wiki/Julius_Petrihttp://en.wikipedia.org/wiki/Robert_Kochhttp://en.wikipedia.org/wiki/Sterilization_(microbiology)http://en.wikipedia.org/wiki/Microbiologyhttp://en.wikipedia.org/wiki/Agar_platehttp://en.wikipedia.org/wiki/Agarhttp://en.wikipedia.org/wiki/Amino_acidhttp://en.wikipedia.org/wiki/Antibiotichttp://en.wikipedia.org/wiki/Antibiotichttp://en.wikipedia.org/wiki/Amino_acidhttp://en.wikipedia.org/wiki/Agarhttp://en.wikipedia.org/wiki/Agar_platehttp://en.wikipedia.org/wiki/Microbiologyhttp://en.wikipedia.org/wiki/Sterilization_(microbiology)http://en.wikipedia.org/wiki/Robert_Kochhttp://en.wikipedia.org/wiki/Julius_Petrihttp://en.wikipedia.org/wiki/Germanyhttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Microbiological_culturehttp://en.wikipedia.org/wiki/Microbiologisthttp://en.wikipedia.org/wiki/Cylindricalhttp://en.wikipedia.org/wiki/Plastichttp://en.wikipedia.org/wiki/Glass


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5ther Petri dish uses do not involve agar2 or instance, cell culture.

6odern Petri dishes oten have rings on the lids and bases whichallow them to be stacked so that they do not slide o# one another.6ultiple dishes can also be incorporated into one plastic container to

create what is called a $multiwell plate$.

As well as making agar plates, empty Petri dishes may be used toobserve plant germination or small animal behaviour, or or otherdaytoday laboratory practices such as drying 7uids in an oven andcarrying and storing samples.
http://en.wikipedia.org/wiki/Cell_culturehttp://en.wikipedia.org/wiki/Agar_platehttp://en.wikipedia.org/wiki/Agar_platehttp://en.wikipedia.org/wiki/Cell_culture


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A growth mediumor culture mediumisa li"uid or gel designed to support thegrowth o microorganismsor cells.

!here are di#erent types o media orgrowing di#erent types o cells. !here are two ma8or types o growth media9

those used or cell culture, which use speci4c

cell types derived rom plants or animals, and microbiological culture, which are used orgrowing microorganisms, such as bacteriaoryeast.
http://en.wikipedia.org/wiki/Microorganismhttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Cell_culturehttp://en.wikipedia.org/wiki/Microbiological_culturehttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Yeasthttp://en.wikipedia.org/wiki/Yeasthttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Microbiological_culturehttp://en.wikipedia.org/wiki/Cell_culturehttp://en.wikipedia.org/wiki/Cell_(biology)http://en.wikipedia.org/wiki/Microorganism


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!he most common growth media ormicroorganisms are nutrient brothsandagar plates2 speciali-ed media are sometimesre"uired or microorganism and cell culturegrowth.%&'

Some organisms, termed fastidiousorganisms, re"uire speciali-ed environmentsdue to complex nutritional re"uirements.

:iruses, or example, are obligatoryintracellular parasitesand re"uire a growthmedium composed o living cells.
http://en.wikipedia.org/wiki/Agar_platehttp://en.wikipedia.org/wiki/Agarhttp://en.wikipedia.org/wiki/Parasitehttp://en.wikipedia.org/wiki/Parasitehttp://en.wikipedia.org/wiki/Agarhttp://en.wikipedia.org/wiki/Agar_plate


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!he most common growth media ormicroorganisms are nutrient broths(li"uid nutrient medium) or

Luria Bertani medium (;< medium orLysogeny Broth). ;i"uid media are oten mixed with agar

and poured into petri dishesto solidiy. !hese agar platesprovide a solid medium

on which microbes may be cultured.


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!he di#erences between growth media usedor cell culture and those used ormicrobiological culture are because cells

derived rom whole organisms and grown inculture oten cannot grow without theaddition o, or instance, hormonesorgrowth actorswhich usually occur in vivo.%='

In the case o animal cells, this di>culty isoten addressed by the addition oblood serumto the medium.
http://en.wikipedia.org/wiki/Hormoneshttp://en.wikipedia.org/wiki/Growth_factorshttp://en.wikipedia.org/wiki/In_vivohttp://en.wikipedia.org/wiki/Blood_serumhttp://en.wikipedia.org/wiki/Blood_serumhttp://en.wikipedia.org/wiki/In_vivohttp://en.wikipedia.org/wiki/Growth_factorshttp://en.wikipedia.org/wiki/Hormones


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In the case o microorganisms, there are nosuch limitations, as they are otenunicellular organisms.

5ne other ma8or di#erence is that animal cellsin culture are oten grown on a 7at surace towhich they attach, and the medium isprovided in a li"uid orm, which covers thecells.

In contrast, bacteria such as Escherichia colimay be grown on solid media or in li"uidmedia.
http://en.wikipedia.org/wiki/Unicellular_organismhttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Unicellular_organism


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An important distinction betweengrowth media types is that o denedversus undenedmedia.


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A de4ned medium will have known "uantitieso all ingredients.

3or microorganisms, they consist o providing

trace elements and vitamins re"uired by themicrobe and especially a de4nedcarbon sourceand nitrogen source.

lucoseor glycerolare oten used as carbonsources, and ammoniumsaltsor nitratesasinorganicnitrogen sources).
http://en.wikipedia.org/wiki/Carbonhttp://en.wikipedia.org/wiki/Nitrogenhttp://en.wikipedia.org/wiki/Glucosehttp://en.wikipedia.org/wiki/Glycerolhttp://en.wikipedia.org/wiki/Ammoniumhttp://en.wikipedia.org/wiki/Salthttp://en.wikipedia.org/wiki/Nitratehttp://en.wikipedia.org/wiki/Inorganichttp://en.wikipedia.org/wiki/Inorganichttp://en.wikipedia.org/wiki/Nitratehttp://en.wikipedia.org/wiki/Salthttp://en.wikipedia.org/wiki/Ammoniumhttp://en.wikipedia.org/wiki/Glycerolhttp://en.wikipedia.org/wiki/Glucosehttp://en.wikipedia.org/wiki/Nitrogenhttp://en.wikipedia.org/wiki/Carbon


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An unde4ned medium has some complexingredients, such as yeast extractor caseinhydrolysate, which consist o a mixture o

many, many chemical species in unknownproportions.

?nde4ned media are sometimes chosenbased on price and sometimes by necessity some microorganisms have never beencultured on de4ned media.
http://en.wikipedia.org/wiki/Yeast_extracthttp://en.wikipedia.org/wiki/Yeast_extract


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A good example o a growth medium is thewortused to make beer.

!he wort contains all the nutrients

re"uired or yeast growth, and underanaerobicconditions, alcohol is produced.

@hen the ermentationprocess iscomplete, the combination o medium anddormant microbes, now beer, is ready orconsumption
http://en.wikipedia.org/wiki/Wort_(brewing)http://en.wikipedia.org/wiki/Beerhttp://en.wikipedia.org/wiki/Anaerobichttp://en.wikipedia.org/wiki/Fermentation_(food)http://en.wikipedia.org/wiki/Fermentation_(food)http://en.wikipedia.org/wiki/Anaerobichttp://en.wikipedia.org/wiki/Beerhttp://en.wikipedia.org/wiki/Wort_(brewing)


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An undened medium(also known as a basalor complexmedium) is a medium that contains9

a carbon source such as glucoseor bacterial growth water various salts needed or bacterial growth a source o amino acids and nitrogen (e.g., bee, yeast

extract)

!his is an unde4ned medium because the amino acidsource contains a variety o compounds with the exact

composition being unknown. utrient media contain all the elements that mostbacteria need or growth and are nonselective, so theyare used or the general cultivation and maintenance obacteria kept in laboratory culture collections.
http://en.wikipedia.org/wiki/Glucosehttp://en.wikipedia.org/wiki/Glucose


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Dened media(also known as chemicallyde4ned media) all the chemicals used are known

does not contain any animal, yeast, plant tissue. Dierential medium

some sort o indicator, typically a dye, is

added, that allows or the di#erentiation oparticular chemical reactions occurringduring growth.


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Minimal media Minimal mediaare those that contain the

minimum nutrients possible or colony

growth, generally without the presence oamino acids, and are oten used bymicrobiologists and geneticists to grow $wildtype$ microorganisms.

6inimal media can also be used to select oror against recombinantsor excon8ugants.
http://en.wikipedia.org/wiki/Recombinanthttp://en.wikipedia.org/wiki/Exconjuganthttp://en.wikipedia.org/wiki/Exconjuganthttp://en.wikipedia.org/wiki/Recombinant


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6inimal medium typically contains9 a carbon source or bacterial growth, which

may be a sugar such as glucose, or a less

energyrich source like succinate various salts, which may vary amongbacteria species and growing conditions2these generally provide essential elementssuch as magnesium, nitrogen, phosphorus,and sulurto allow the bacteria to synthesi-eproteinand nucleic acid

water
http://en.wikipedia.org/wiki/Glucosehttp://en.wikipedia.org/wiki/Succinatehttp://en.wikipedia.org/wiki/Magnesiumhttp://en.wikipedia.org/wiki/Nitrogenhttp://en.wikipedia.org/wiki/Phosphorushttp://en.wikipedia.org/wiki/Sulfurhttp://en.wikipedia.org/wiki/Proteinhttp://en.wikipedia.org/wiki/Nucleic_acidhttp://en.wikipedia.org/wiki/Nucleic_acidhttp://en.wikipedia.org/wiki/Proteinhttp://en.wikipedia.org/wiki/Sulfurhttp://en.wikipedia.org/wiki/Phosphorushttp://en.wikipedia.org/wiki/Nitrogenhttp://en.wikipedia.org/wiki/Magnesiumhttp://en.wikipedia.org/wiki/Succinatehttp://en.wikipedia.org/wiki/Glucose


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Supplementary minimal media are a type o minimal media that also

contains a single selected agent, usually

an amino acidor a sugar. !his supplementation allows or the

culturing o speci4c lines o auxotrophicrecombinants.
http://en.wikipedia.org/wiki/Amino_acidhttp://en.wikipedia.org/wiki/Sugarhttp://en.wikipedia.org/wiki/Auxotrophichttp://en.wikipedia.org/wiki/Recombinanthttp://en.wikipedia.org/wiki/Recombinanthttp://en.wikipedia.org/wiki/Auxotrophichttp://en.wikipedia.org/wiki/Sugarhttp://en.wikipedia.org/wiki/Amino_acid


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;ysogeny


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6annitol salt agar(6SA) 6SA is also a selective and di#erential media.

6annitolis the di#erential part, it indicates

organisms that erment mannitol. I mannitolermentation is occurring, lactic acid will beproduced, and the pD will drop causing the6SA plate to turn yellow. !he salt portion isselective or halophiles2 organisms thatcannot withstand a high salt content will beunable to grow well. 6uellerDinton agar(6DA)
http://en.wikipedia.org/wiki/Mannitol_salt_agarhttp://en.wikipedia.org/wiki/Mannitolhttp://en.wikipedia.org/wiki/Halophilehttp://en.wikipedia.org/wiki/Mueller-Hinton_agarhttp://en.wikipedia.org/wiki/Mueller-Hinton_agarhttp://en.wikipedia.org/wiki/Halophilehttp://en.wikipedia.org/wiki/Mannitolhttp://en.wikipedia.org/wiki/Mannitol_salt_agar


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6DA contains bee inusion, peptone, and starchused primarily or antibiotic susceptibilitytesting. It can be in a orm o blood agar.

3ungi growing in axenic culture (ascomycetes) utrient agar utrient agar is usually used or growth o non

astidious organisms and observation opigment production. It is sae to use in schoolscience laboratories because it does notselectively grow pathogenicbacteria.
http://en.wikipedia.org/wiki/Ascomyceteshttp://en.wikipedia.org/wiki/Nutrient_agarhttp://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Nutrient_agarhttp://en.wikipedia.org/wiki/Ascomycetes


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Selective mediaare used or the growth o onlyselect microorganisms.

3or example, i a microorganism is resistant to acertain antibiotic, such as ampicillinor

tetracycline, then that antibiotic can be added tothe medium in order to prevent other cells, whichdo not possess the resistance, rom growing.

6edia lacking an amino acidsuch as prolinein

con8unction with E coliunable to synthesi-e itwere commonly used by geneticists beore theemergence o genomicsto mapbacterialchromosomes.
http://en.wikipedia.org/wiki/Antibiotichttp://en.wikipedia.org/wiki/Ampicillinhttp://en.wikipedia.org/wiki/Tetracyclinehttp://en.wikipedia.org/wiki/Amino_acidhttp://en.wikipedia.org/wiki/Prolinehttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Genomicshttp://en.wikipedia.org/w/index.php?title=Chromosome_mapping&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Chromosome_mapping&action=edit&redlink=1http://en.wikipedia.org/wiki/Genomicshttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Prolinehttp://en.wikipedia.org/wiki/Amino_acidhttp://en.wikipedia.org/wiki/Tetracyclinehttp://en.wikipedia.org/wiki/Ampicillinhttp://en.wikipedia.org/wiki/Antibiotic


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Selective growth media are also used incell cultureto ensure the survival orprolieration o cells with certain properties,such as antibiotic resistanceor the ability tosynthesi-e a certain metabolite.

ormally, the presence o a speci4c geneor

an alleleo a gene coners upon the cell theability to grow in the selective medium. Insuch cases, the gene is termed a marker.
http://en.wikipedia.org/wiki/Cell_culturehttp://en.wikipedia.org/wiki/Antibiotic_resistancehttp://en.wikipedia.org/wiki/Metabolitehttp://en.wikipedia.org/wiki/Genehttp://en.wikipedia.org/wiki/Allelehttp://en.wikipedia.org/wiki/Genetic_markerhttp://en.wikipedia.org/wiki/Genetic_markerhttp://en.wikipedia.org/wiki/Allelehttp://en.wikipedia.org/wiki/Genehttp://en.wikipedia.org/wiki/Metabolitehttp://en.wikipedia.org/wiki/Antibiotic_resistancehttp://en.wikipedia.org/wiki/Cell_culture


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Selective growth media or eukaryoticcellscommonly contain neomycinto select cellsthat have been successully transectedwith a plasmid carrying the neomycinresistance gene as a marker.

ancyclovir is an exception to the rule as it

is used to speci4cally kill cells that carry itsrespective marker, the Derpes simplex virusthymidine kinase (DS: !+).
http://en.wikipedia.org/wiki/Eukaryotichttp://en.wikipedia.org/wiki/Neomycinhttp://en.wikipedia.org/wiki/Transfectionhttp://en.wikipedia.org/wiki/Herpes_simplex_virushttp://en.wikipedia.org/wiki/Herpes_simplex_virushttp://en.wikipedia.org/wiki/Transfectionhttp://en.wikipedia.org/wiki/Neomycinhttp://en.wikipedia.org/wiki/Eukaryotic


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Some examples o selective media include9 eosinmethylen blue agar (B6


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6ac1onkey agaror ramnegativebacteria

Dektoen Bnteric (DB) which is selective or

ramnegative bacteria 6annitol Salt Agar (6SA) which is

selective or rampositive bacteria anddi#erential or mannitol

!erri4c


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xylose lysine desoxyscholate (G;C),which is selective or ramnegativebacteria


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3our types o agar platesdemonstrating di#erential growthdepending on bacterial metabolism.


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Dierential mediaor indicator mediadistinguish one microorganism type romanother growing on the same media.

!his type o media uses the biochemical

characteristics o a microorganism growing inthe presence o speci4c nutrients orindicators (such as neutral red, phenol red,eosin y, or methylene blue) added to themedium to visibly indicate the de4ning

characteristics o a microorganism. !his type o media is used or the detection o

microorganisms and by molecular biologiststo detect recombinantstrains o bacteria.
http://en.wikipedia.org/wiki/Neutral_redhttp://en.wikipedia.org/wiki/Phenol_redhttp://en.wikipedia.org/wiki/Eosinhttp://en.wikipedia.org/wiki/Methylene_bluehttp://en.wikipedia.org/wiki/Recombinanthttp://en.wikipedia.org/wiki/Recombinanthttp://en.wikipedia.org/wiki/Methylene_bluehttp://en.wikipedia.org/wiki/Eosinhttp://en.wikipedia.org/wiki/Phenol_redhttp://en.wikipedia.org/wiki/Neutral_red


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Bxamples o di#erential media include9 Bosin methylene blue(B6


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!hese are used or the temporarystorage o specimens being transportedto the laboratory or cultivation.

Such media ideally maintain theviability o all organisms in thespecimen without altering their

concentration.


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!ransport media typically contain onlybu#ers and salt.

!he lack o carbon, nitrogen, and

organic growth actors preventsmicrobial multiplication.

!ransport media used in the isolation o

anaerobes must be ree o molecularoxygen. Bxample 9stuart transportmedium.


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Bnriched media contain the nutrientsre"uired to support the growth o awide variety o organisms, including

some o the more astidious ones. !hey are commonly used to harvest as

many di#erent types o microbes as are

present in the specimen.


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Blood agaris an enriched medium inwhich nutritionally rich whole bloodsupplements the basic nutrients.

!hocolate agaris enriched with heattreated blood (/J01), which turnsbrown and gives the medium the color

or which it is named.
http://en.wikipedia.org/wiki/Blood_agarhttp://en.wikipedia.org/wiki/Chocolate_agarhttp://en.wikipedia.org/wiki/Chocolate_agarhttp://en.wikipedia.org/wiki/Blood_agar


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MacConkey(also McConkey) agar is aculturemediumdesigned to growramnegativebacteriaand stainthem orlactose ermentation.

Contents It contains bile salts(to inhibit most rampositive

bacteria, except Enterococcusand some specieso Staphylococcus), crystal violetdye (which alsoinhibits certain rampositive bacteria),neutral reddye (which stains microbes ermentinglactose), lactoseand peptone.
http://en.wikipedia.org/wiki/Microbiological_culturehttp://en.wikipedia.org/wiki/Selective_mediumhttp://en.wikipedia.org/wiki/Gram-negativehttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Staininghttp://en.wikipedia.org/wiki/Industrial_fermentationhttp://en.wikipedia.org/wiki/Bile_saltshttp://en.wikipedia.org/wiki/Gram-positivehttp://en.wikipedia.org/wiki/Enterococcushttp://en.wikipedia.org/wiki/Staphylococcushttp://en.wikipedia.org/wiki/Crystal_violethttp://en.wikipedia.org/wiki/Neutral_redhttp://en.wikipedia.org/wiki/Lactosehttp://en.wikipedia.org/wiki/Peptonehttp://en.wikipedia.org/wiki/Peptonehttp://en.wikipedia.org/wiki/Lactosehttp://en.wikipedia.org/wiki/Neutral_redhttp://en.wikipedia.org/wiki/Crystal_violethttp://en.wikipedia.org/wiki/Staphylococcushttp://en.wikipedia.org/wiki/Enterococcushttp://en.wikipedia.org/wiki/Gram-positivehttp://en.wikipedia.org/wiki/Bile_saltshttp://en.wikipedia.org/wiki/Industrial_fermentationhttp://en.wikipedia.org/wiki/Staininghttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Gram-negativehttp://en.wikipedia.org/wiki/Selective_mediumhttp://en.wikipedia.org/wiki/Microbiological_culture


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6ac 1onkey agar with lactose andnonlactose ermenters

A 6ac1onkey agar plate with anactive bacterial culture.


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Alred !heodore 6ac1onkeydevelopedit while working as a bacteriologist orthe *oyal 1ommission on Sewage

Cisposal.
http://en.wikipedia.org/wiki/Alfred_Theodore_MacConkeyhttp://en.wikipedia.org/wiki/Alfred_Theodore_MacConkey


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Acting as a visual pDindicator, the agardistinguishes those ramnegative bacteriathat can erment the sugar lactose (;acK)rom those that cannot (;ac).


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on;actose ermenting bacteria suchas Salmonella, Proteus speciesandShigellacannot utili-e lactose, and will

use peptone instead.

!his orms ammonia, which raises the

pD o the agar, and leads to theormation o whiteMcolorless colonies.
http://en.wikipedia.org/wiki/Salmonellahttp://en.wikipedia.org/wiki/Proteus_(bacterium)http://en.wikipedia.org/wiki/Shigellahttp://en.wikipedia.org/wiki/Ammoniahttp://en.wikipedia.org/wiki/Agarhttp://en.wikipedia.org/wiki/Agarhttp://en.wikipedia.org/wiki/Ammoniahttp://en.wikipedia.org/wiki/Shigellahttp://en.wikipedia.org/wiki/Proteus_(bacterium)http://en.wikipedia.org/wiki/Salmonella


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!hus, by selecting or ramnegativebacteria and di#erentiating between entericpathogens such as E coliand Salmonella,the 6ac1onkey agar is readily implementedin the clinical diagnosis o diarrhea.

!his medium is also known as an $indicator

medium$ and a $low selective medium$.Absence o electrolytes serves to inhibitswarming by Proteus species
http://en.wikipedia.org/wiki/Enterichttp://en.wikipedia.org/wiki/Diarrheahttp://en.wikipedia.org/wiki/Diarrheahttp://en.wikipedia.org/wiki/Enteric


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Cetrimide agaris a type o agarused or theselective isolation o the gramnegativebacteria,Pseudomonas aeruginosa.

As the name suggests, it contains cetrimide, whichis the selective agent against alternate microbial7ora.

1etrimide also inhances the production oPseudomonaspigments such as pyocyanin and7uorescein, which show a characteristic bluegreen and yellowgreen colour, respectively.

%='%' 1etrimide agar is widely used in the examination

o cosmetics, pharmaceuticals and clinicalspecimens to test or the presence oPseudomonas aeruginosa
http://en.wikipedia.org/wiki/Agarhttp://en.wikipedia.org/wiki/Gram-negativehttp://en.wikipedia.org/wiki/Pseudomonas_aeruginosahttp://en.wikipedia.org/wiki/Cetrimidehttp://en.wikipedia.org/wiki/Fluoresceinhttp://en.wikipedia.org/wiki/Fluoresceinhttp://en.wikipedia.org/wiki/Cetrimidehttp://en.wikipedia.org/wiki/Pseudomonas_aeruginosahttp://en.wikipedia.org/wiki/Gram-negativehttp://en.wikipedia.org/wiki/Agar


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Xyloselysinedeoxycholateagar(G;Cagar) is a selectivegrowth mediumused inthe isolation o Salmonellaand Shigellaspecies rom clinical samples and rom ood.

It has a pDo approximately N., leaving itwith a bright pink or red appearance due tothe indicator phenol red.

Sugar ermentation lowers the pD and the

phenol red indicator registers this bychanging to yellow.

.
http://en.wikipedia.org/wiki/Xylosehttp://en.wikipedia.org/wiki/Lysinehttp://en.wikipedia.org/wiki/Deoxycholatehttp://en.wikipedia.org/wiki/Agarhttp://en.wiktionary.org/wiki/selectivehttp://en.wikipedia.org/wiki/Growth_mediumhttp://en.wikipedia.org/wiki/Salmonellahttp://en.wikipedia.org/wiki/Shigellahttp://en.wikipedia.org/wiki/PHhttp://en.wikipedia.org/wiki/PHhttp://en.wikipedia.org/wiki/Shigellahttp://en.wikipedia.org/wiki/Salmonellahttp://en.wikipedia.org/wiki/Growth_mediumhttp://en.wiktionary.org/wiki/selectivehttp://en.wikipedia.org/wiki/Agarhttp://en.wikipedia.org/wiki/Deoxycholatehttp://en.wikipedia.org/wiki/Lysinehttp://en.wikipedia.org/wiki/Xylose


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6ost gut bacteria, including Salmonella, can ermentthe sugar xylose to produce acid2 Shigellacoloniescannot do this and thereore remain red.

Ater exhausting the xylose supply Salmonella

colonies will decarboxylate lysine, increasing the pDonce again to alkaline and mimicking the red Shigellacolonies.

Salmonellae metabolise thiosulate to producehydrogen sul4de, which leads to the ormation ocolonies with black centers and allows them to bedi#erentiated rom the similarly coloured Shigellacolonies
http://en.wikipedia.org/wiki/Hydrogen_sulfidehttp://en.wikipedia.org/wiki/Hydrogen_sulfide


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5ther Bnterobacteria such as E coliwillerment the lactose and sucrose present inthe medium to an extent that will preventpD reversion by decarboxylation and

acidiy the medium turning it yellow. Salmonellaspecies9 red colonies, some

with black centers. Shigellaspecies9 red colonies. 1oliorms9 yellow to orange colonies. Pseudomonas aeruginosa9 pink, 7at, rough

colonies
http://en.wikipedia.org/wiki/Coliformhttp://en.wikipedia.org/wiki/Pseudomonas_aeruginosahttp://en.wikipedia.org/wiki/Pseudomonas_aeruginosahttp://en.wikipedia.org/wiki/Coliform


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Feast extract =gMl;;ysine JgMl

Gylose =.NJgMl

;actose N.JgMl

Sucrose N.JgMlSodium deoxycholate &gMl

Sodium chloride JgMl

Sodium thiosulate .LgMl

3erricammoniumcitrate /.LmgMlPhenol red /./LgMl

Agar &O.JgM
http://en.wikipedia.org/wiki/Yeast_extracthttp://en.wikipedia.org/wiki/Lysinehttp://en.wikipedia.org/wiki/Xylosehttp://en.wikipedia.org/wiki/Lactosehttp://en.wikipedia.org/wiki/Sucrosehttp://en.wikipedia.org/wiki/Deoxycholatehttp://en.wikipedia.org/wiki/Sodium_chloridehttp://en.wikipedia.org/wiki/Sodium_thiosulfatehttp://en.wikipedia.org/wiki/Ferrichttp://en.wikipedia.org/wiki/Ammoniumhttp://en.wikipedia.org/wiki/Citratehttp://en.wikipedia.org/wiki/Phenol_redhttp://en.wikipedia.org/wiki/Agarhttp://en.wikipedia.org/wiki/Agarhttp://en.wikipedia.org/wiki/Phenol_redhttp://en.wikipedia.org/wiki/Citratehttp://en.wikipedia.org/wiki/Ammoniumhttp://en.wikipedia.org/wiki/Ferrichttp://en.wikipedia.org/wiki/Sodium_thiosulfatehttp://en.wikipedia.org/wiki/Sodium_chloridehttp://en.wikipedia.org/wiki/Deoxycholatehttp://en.wikipedia.org/wiki/Sucrosehttp://en.wikipedia.org/wiki/Lactosehttp://en.wikipedia.org/wiki/Xylosehttp://en.wikipedia.org/wiki/Lysinehttp://en.wikipedia.org/wiki/Yeast_extract


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nQ- agar nQ- agar allows more rapid bacteriological

diagnosis as Salmonellaand Shigellacolonies canbe clearly and reliably di#erentiated rom otherBnterobacteriaceae. !he yields o Salmonellaromstool samples obtained, when using this medium,are higher than those obtained with ;BI3S5 Agaror SalmonellaEShigella agar (SSA).Phenylethyl alcohol agar(PBA)

PBA selects or Staphylococcusspecies while

inhibiting ramnegativebacilli (e.g. Escherichia coli, Shigella, Proteus, etc.). 6SA is selective orStaphylococcusPBA is selective or gram positivebacteria
http://en.wikipedia.org/w/index.php?title=%C3%96n%C3%B6z_agar&action=edit&redlink=1http://en.wikipedia.org/wiki/Salmonellahttp://en.wikipedia.org/wiki/Shigellahttp://en.wikipedia.org/wiki/Enterobacteriaceaehttp://en.wikipedia.org/w/index.php?title=Phenylethyl_alcohol_agar&action=edit&redlink=1http://en.wikipedia.org/wiki/Staphylococcushttp://en.wikipedia.org/wiki/Gram-negativehttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Shigellahttp://en.wikipedia.org/wiki/Proteus_(bacterium)http://en.wikipedia.org/wiki/Proteus_(bacterium)http://en.wikipedia.org/wiki/Shigellahttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Gram-negativehttp://en.wikipedia.org/wiki/Staphylococcushttp://en.wikipedia.org/w/index.php?title=Phenylethyl_alcohol_agar&action=edit&redlink=1http://en.wikipedia.org/wiki/Enterobacteriaceaehttp://en.wikipedia.org/wiki/Shigellahttp://en.wikipedia.org/wiki/Salmonellahttp://en.wikipedia.org/w/index.php?title=%C3%96n%C3%B6z_agar&action=edit&redlink=1


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*OA Agar(*OA) A nonspeci4c agar that imitates the medium o

water. ?sed or water analysis.!ryptic (!rypticase) Soy Agar(!SA)

!SA is a general purpose media produced viaen-ymatic digestion o soybeanmeal and casein2 !SA is re"uently the base media o other agarplate type, i.e. blood agar plates (


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Gylose;ysineCeoxycholate agar(G;C) G;C is used or the culture o stoolsamples, and

contains two indicators. It is ormulated toinhibit rampositive bacteria, while the growth

o ramnegative bacilliis encouraged. !hecolonies o lactose ermenters appear yellow. Itis also used to culture possible Salmonellathatmay be present in a ood sample. Salmonellacolonies will show a black halo on G;C.

1etrimide agar 1etrimide agar is a type o agar used or theselective isolation o the gramnegativebacteria, Pseudomonas aeruginosa
http://en.wikipedia.org/wiki/XLD_agarhttp://en.wikipedia.org/wiki/Stoolhttp://en.wikipedia.org/wiki/Bacillihttp://en.wikipedia.org/wiki/Salmonellahttp://en.wikipedia.org/wiki/Salmonellahttp://en.wikipedia.org/wiki/Bacillihttp://en.wikipedia.org/wiki/Stoolhttp://en.wikipedia.org/wiki/XLD_agar


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Sabouraud agar Sabouraud agar is used to culture ungi and

has a low pD that inhibits the growth o mostbacteria2 also contains the antibioticgentamicin to speci4cally inhibit the growth oramnegative bacteria. Day Inusion agar

Speci4c or the culturing o slime moulds

(though not technically ungi). Potato dextroseagar PCA is used to culture o certain types o ungi.


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growth medium

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