Pyruvate Broth Test- Principle, Procedure, Results, Uses

Pyruvate Broth Test

Objectives of Pyruvate Broth Test To determine the ability of an organism to utilize pyruvate. It aids in the differentiation between Enterococcus faecalis and Enterococcus faecium. Principle of Pyruvate Broth Test In the identification of microorganisms, the widely used method is the ability of bacteria to form organic compounds by metabolizing certain carbohydrates and related compounds. Pyruvate broth is a carbohydrate-free, nutrient-limited medium. Pyruvate Broth contains casein peptone, sodium chloride, yeast extract, dipotassium phosphate, sodium pyruvate, and bromothymol blue. Casein peptone and … Read more

Sulfur Reduction Test- Principle, Procedure, Results, Uses

Sulfur Reduction Test

Objectives of Sulfur Reduction Test To determine the ability of the organism to reduce sulfur for the production of hydrogen sulfide. To differentiate members of Enterobacteriaceae, especially the sulfur-reducing Salmonella and Proteus from the non-reducing Morganella morganii and Providencia rettgeri. Principle of Sulfur Reduction Test The Sulfur Reduction Test is performed using the SIM medium. SIM medium also tests for indole production and motility. It is a semi-solid medium that is formulated with casein and animal tissue as sources of … Read more

Salt Tolerance Test- Principle, Procedure, Results, Limitations

Salt Tolerance Test

Objectives of Salt Tolerance Test To determine the ability of an organism to grow in high concentrations of salt. It is used for the differentiation of Enterococci from Non-Enterococci. Principle of Salt Tolerance Test Salt acts as a selective agent and interferes with membrane permeability and osmotic equilibrium. The salt tolerance medium is a selective and differential medium in which salt-tolerant organisms will produce heavy growth in the broth and on solid agar within 48 hours. Hajna devised the first … Read more

Kligler Iron Agar Test- Principle, Media, Procedure, Results, Uses

Kligler Iron Agar Test

Objective To differentiate the enteric gram-negative bacilli based on the production of hydrogen sulfide and fermentation of dextrose and lactose. Principle of Kligler Iron Agar Test Kligler Iron Agar (KIA) test is used in differentiating certain members of the Enterobacteriaceae by demonstrating hydrogen sulfide production and the fermentation of dextrose and lactose. Kligler agar used for the test comprises casein and meat peptones that supply nitrogenous compounds and amino acids, vitamins necessary for bacterial growth. The medium comprises two sources … Read more

Acetamide Utilization Test- Principle, Procedure, Results, Uses

Acetamide Utilization Test- Principle, Procedure and Expected Results

What is Acetamide Utilization Test? The Acetamide utilization test is one of the many biochemical tests performed for the identification of aerobic organisms. This test is based on the utilization of acetamide by the organism via the process of deamidation. The deamidation process occurs in the presence of acylamidase enzyme. An Acetamide utilization test is performed for the distinction between the fermentative group of organisms and the oxidative group of organisms. This has been commonly used for the differentiation or … Read more

Biochemical Test of Escherichia coli (E. coli)

Biochemical Test of Escherichia coli (E. coli)

Biochemical Test of Escherichia coli (E. coli) Basic Characteristics Properties (E. coli) Capsule Capsulated Catalase Positive (+ve) Citrate Negative (-ve) Coagulase Negative (-ve) Flagella Flagellated Gas Positive (+ve) Gelatin Hydrolysis Negative (-ve) Gram Staining Negative (-ve) Growth in KCN Negative (-ve) H2S Negative (-ve) Hemolysis Negative (-ve) Indole Positive (+ve) Motility Motile MR (Methyl Red) Positive (+ve) Nitrate Reduction Positive (+ve) OF (Oxidative-Fermentative) Fermentative Oxidase Negative (-ve) Pigment Negative (-ve) PYR Negative (-ve) Shape Rod Spore Non-Sporing TSIA (Triple Sugar … Read more

Biochemical Test of Enterobacter cloacae

Biochemical Test of Enterobacter cloacae ­Basic Characteristics Properties (Enterobacter cloacae) Capsule Negative (-ve) Catalase Positive (+ve) Citrate Positive (+ve) Flagella Positive (+ve) Gas from glucose Positive (+ve) Gelatin Hydrolysis Negative (-ve) Gram Staining Negative (-ve) Growth in KCN Positive (+ve) H2S Negative (-ve) Indole Negative (-ve) Motility Motile MR (Methyl Red) Negative (-ve) Nitrate Reduction Positive (+ve) OF (Oxidative-Fermentative) Facultative Anaerobes Oxidase Negative (-ve) Pigment Negative (-ve) Shape Rods Spore Negative (-ve) Urease Negative (-ve) VP (Voges Proskauer) Positive (+ve) … Read more

Biochemical Test of Bacillus anthracis

Biochemical Test of Bacillus anthracis

Biochemical Test of Bacillus anthracis ­Basic Characteristics Properties (Bacillus anthracis) Capsule Capsulated Catalase Positive (+ve) Gas Negative (-ve) Gelatin Hydrolysis Positive (+ve) Gram Staining Positive (+ve) Hemolysis Negative (-ve) Indole Positive (+ve) Motility Negative (-ve) Nitrate Reduction Positive (+ve) Oxidase Negative (-ve) Pigment Negative (-ve) Shape Rods Spore Positive (+ve) Urease Negative (-ve) VP (Voges Proskauer) Positive (+ve) Fermentation of Adonitol Negative (-ve) Arabinose Negative (-ve) Arabitol Negative (-ve) Cellobiose Negative (-ve) Dulcitol Negative (-ve) Erythritol Negative (-ve) Fructose Variable … Read more

Biochemical Test of Staphylococcus epidermidis

Biochemical Test of Staphylococcus epidermidis

Biochemical Test of Staphylococcus epidermidis ­Basic Characteristics Properties (Staphylococcus epidermidis) Capsule Mostly Capsulated Catalase Positive (+ve) Citrate Negative (-ve) Coagulase Negative (-ve) Gas Positive (+ve) Gelatin Hydrolysis Negative (-ve) Gram Staining Positive (+ve) H2S Positive (+ve) Hemolysis Negative (-ve) Motility Negative (-ve) MR (Methyl Red) Negative (-ve) Nitrate Reduction Positive (+ve) Oxidase Negative (-ve) Pigment Negative (-ve) Shape Cocci Urease Positive (+ve) VP (Voges Proskauer) Positive (+ve) Fermentation of Arabinose Negative (-ve) Cellobiose Negative (-ve) DNase Negative (-ve) Dulcitol Negative … Read more

Biochemical Test of Serratia marcescens

Biochemical Test of Serratia marcescens

Biochemical Test of Serratia marcescens ­Basic Characteristics Properties (Serratia marcescens) Capsule Negative (-ve) Catalase Positive (+ve) Citrate Positive (+ve) Flagella Positive (+ve) Gas Variable Gelatin Hydrolysis Positive (+ve) Gram Staining Negative (-ve) H2S Negative (-ve) Indole Negative (-ve) Motility Positive (+ve) MR (Methyl Red) Negative (-ve) Nitrate Reduction Positive (+ve) OF (Oxidative-Fermentative) Facultative Anaerobes Oxidase Negative (-ve) Pigment Positive (+ve) Shape Rods Spore Negative (-ve) Urease Positive (+ve) VP (Voges Proskauer) Positive (+ve) Fermentation of Adonitol Positive (+ve) Arabinose Negative … Read more