Archives for Tests for identification of bacteria
Oxidative/Fermentative Test (O/F test)
Oxidative/Fermentative (O/F) test is done to distinguish between aerobes and anaerobes through their ability to breakdown carbohydrates. In this test, a semi solid medium containing a carbohydrate (usually glucose) and…
Novobiocin susceptibility test
The speciation of coagulase negative Staphylococcus is necessary in certain culture specimens. Coagulase negative staphylococci can either be resistant or susceptible to novobiocin. The one most commonly isolated novobiocin resistant…
Bile solubility test: Principle, Procedure and Expected results
Principle of Bile Solubility test: Bile solubility test is used to differentiate Streptococcus pneumoniae from other alpha-hemolytic Streptococci. Streptococcus pneumoniae is bile soluble whereas all other alpha-hemolytic streptococci are insoluble. Bile…
CAMP test and Reverse CAMP test
CAMP (Christie, Atkins, and Munch-Peterson) test is used for the presumptive identification of Group B Streptococcus (Streptococcus agalactiae). It is the only beta-hemolytic Streptococcus which yields a positive CAMP test. The…
Leucine amino peptidase (LAP) test for identification of catalase negative gram positive cocci
Principle of Leucine amino peptidase (LAP) test: Leucine amino peptidase (LAP) test is used for the preliminary characterization of catalase negative, gram-positive cocci. This is a rapid test for detection…
Gelatin hydrolysis test: Principle, Procedure, Interpretation and preparation of nutrient gelatin medium
Gelatin hydrolysis is helpful in identifying and differentiating species of Bacillus, Clostridium, Proteus, Pseudomonas, and Serratia. It also distinguishes the gelatinase-positive, pathogenic Staphylococcus aureus from the gelatinase-negative, non-pathogenic S. epidermidis…
Hippurate hydrolysis test
Hippurate hydrolysis test can be used for presumptive identification of Gardnerella vaginalis, Campylobacter jejuni, Listeria monocytogenes and group B streptococci. Principle of Hippurate hydrolysis test Hippurate hydrolysis test is used to detect the ability…
Triple Sugar Iron Agar test (TSI test): Principle, Procedure and Interpretation
Principle: Triple sugar iron agar test is used to determine whether gram negative bacilli utilise glucose and lactose or sucrose fermentatively and produce hydrogen sulfide (H2S). It contains 10 parts…
Citrate utilisation test: Principle, Procedure and Expected results
Principle Citrate utilisation test is used to detect the ability of an organism to utilize sodium citratre as a sole source of carbon and ammonium salt as a sole source…
Coagulase test: Principle, Procedure and Interpretation
Coagulase test is done to distinguish Staphylococcus aureus from other Coagulase negative Staphylococci (CONS) like Staphylococcus epidermidis, Staphylococcus saprophyticus etc. Staphylococcus aureus produces two types of coagulase, free coagulase and bound…