Biochemical Test Archives

Acetamide Utilization Test- Principle, Procedure, Results, Uses

October 4, 2020 by Anupama Sapkota

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 …

Pyruvate Broth Test

February 4, 2021December 17, 2019 by Sagar Aryal

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 …

Sulfur Reduction Test

January 1, 2020December 13, 2019 by Sagar Aryal

Objectives 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 The Sulfur Reduction Test is performed using the SIM medium. SIM medium also tests for indole production and motility. It is a semi-solid …

Salt Tolerance Test

February 4, 2021November 28, 2019 by Sagar Aryal

Objectives 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 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 …

Kligler Iron Agar Test

February 4, 2021November 25, 2019 by Sagar Aryal

Objective To differentiate the enteric gram-negative bacilli based on the production of hydrogen sulfide and fermentation of dextrose and lactose. Principle 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 of casein and meat peptones that …

Biochemical Test of Burkholderia cepacia

February 4, 2021October 28, 2019 by Sagar Aryal

a: Burkholderia cepacia ATCC (Image Source: ATCC) b: Burkholderia cepacia (Image Source: Rapid Microbiology) c: Burkholderia cepacia (Image Source: OMICS International) d: Burkholderia cepacia complex from respiratory secretions of patients with cystic fibrosis (Image Source: Thermo Scientific) e: Scanning Electron Micrograph of Burkholderia cepacia (Image Source: Wikipedia) f: Burkholderia cepacia gram stain (Image Source: DOI: 10.1099/jmmcr.0.005081) Some of the characteristics …

Biochemical Test of Klebsiella granulomatis

February 4, 2021October 14, 2019 by Sagar Aryal

Image: Granuloma inguinale (donovanosis) in a conventional Pap test. A: Granulomatous inflammation is shown with epithelioid histiocytes and lymphocytes. B: The organisms (Donovan bodies) can be seen in thin-walled intracytoplasmic vacuoles (circle ). (Pap stain, Mag ×200 in a and ×400 in b). C: Macrophages show numerous safety pin-shaped structures with polar thickening of chromatin (Donovan bodies) and a halo …

Biochemical Test of Haemophilus parainfluenzae

February 4, 2021September 15, 2019 by Sagar Aryal

Some of the characteristics are as follows: Basic Characteristics Properties (Haemophilus parainfluenzae) Capsule Variable Catalase Variable Gas Variable Gram Staining Gram-negative (-ve) H2S Positive (+ve) Hemolysis Negative (-ve) Indole Variable Motility Negative (-ve) Nitrate Reduction Positive (+ve) Nitrite Reduction Positive (+ve) Oxidase Positive (+ve) Shape Small, pleomorphic rods, usually with long, ﬁlamentous forms. Urease Variable V-factor requirement Positive (+ve) Fermentation …

Biochemical Test of Francisella tularensis subsp. tularensis

February 4, 2021August 13, 2019 by Sagar Aryal

Image Source: New York State Health Department Some of the characteristics are as follows: Basic Characteristics Properties (Francisella tularensis subsp. tularensis) Capsule Positive (+ve) Catalase Positive (+ve) Flagella Negative (-ve) Gas Negative (-ve) Gelatin Hydrolysis Negative (-ve) Gram Staining Faintly stained Gram-negative H2S (in cysteine-supplemented medium) Positive (+ve) Indole Negative (-ve) Motility Negative (-ve) Nitrate Reduction Negative (-ve) NH3 produced …

Biochemical Test of Burkholderia pseudomallei

February 4, 2021April 24, 2019 by Sagar Aryal

Image Source: University of Cambridge Some of the characteristics are as follows: Basic Characteristics Properties (Burkholderia pseudomallei) Capsule Positive (+ve) Catalase Positive (+ve) Citrate Positive (+ve) Flagella Positive (+ve) Gas Negative (-ve) Gelatin Hydrolysis Positive (+ve) Gram Staining Gram-negative (-ve) H2S Negative (-ve) Indole Negative (-ve) Motility Positive (+ve) Nitrate Reduction Positive (+ve) Oxidase Positive (+ve) Pigment Negative (-ve) Shape …