LaboratoryDiagnosis 213
FractionatedInoculationofNutrientAgar
Fig.3. 33 Isolated colo-
niesareobtainedbymeans
offractionatedinoculation
ofnutrientagar.Thewire
loopmustbesterilizedbe-
tweeninoculations.
BloodAgarPlateFollowingFractionatedInoculationandIncubation
Fig.3. 34 Bloodagarisfre-
quentlyusedasauniversal
enrichmentmedium.Most
humanbacterialpathogens
growonit.Hereisapurecul-
tureofStaphylococcusaur-
eus.
EndoAgarFollowingFractionatedInoculationwithaMixedCulture
Fig.3. 35 Endo agar is a
combined selective/indica-
tormedium.Itallowsgrowth
ofEnterobacteriaceae,Pseu-
domonadaceae, and other
Gram-negativerodbacteria
butinhibitsthegrowthof
Gram-positivebacteriaand
Gram-negative cocci. The
red color of the colonies
andagarischaracteristicof
lactosebreakdown(=Escher-
ichiacoli);thelight-coloredcoloniesarelactose-negative(=Salmonellaenterica).
3
Kayser, Medical Microbiology © 2005 Thieme