Practical - Biology Notes Online

Growth at 42 Test – Growth of Non Fermentative Bacteria at 42°C

Published on May 11, 2024 Written by BNO Team

Test Name Growth at 42 Test Purpose This test distinguishes pyocyanogenic pseudomonas from other Pseudomonas species.Determine an organism’s capacity to live at a temperature of 42°C.To distinguish fermentative bacteria from non-fermentative bacteria. Uses The test is used to determine an organism’s capacity to grow at 42°C.This test distinguishes pyocyanogenic pseudomonas from other Pseudomonas species. Result … Read more

Sulfur Reduction Test – Principle, Purpose, Procedure, Result

Published on May 10, 2024 Written by BNO Team

What is Sulfur Reduction Test? Definition of Sulfur Reduction Test The Sulfur Reduction Test is a biochemical assay used to determine the ability of microorganisms to metabolize sulfur-containing compounds, resulting in the production of hydrogen sulfide (H2S) gas. This test aids in differentiating and identifying bacterial species based on their sulfur-reducing capabilities. Objective of Sulfur … Read more

Salt Tolerance Test – Principle, Purpose, Procedure, Result

Published on May 10, 2024 Written by BNO Team

The ability to develop in the presence of varying concentrations of sodium chloride (NaCl) has been used to distinguish between various bacteria.

Pyruvate Broth Test Principle, Purpose, Procedure, Result

Published on May 10, 2024 Written by BNO Team

Pyruvate Broth Test Purpose Pyruvate Broth Test Principle Requirement Pyruvate Broth Composition Pancreatic digest of casein (10 gm/L) sodium pyruvate (10 gm/L) yeast extract (5 gm/L) NaCl (5 gm/L) dipotassium Phosphate K2HPO4 (5 gm/L) bromothymol blue (0.04 gm/L) pH 7.3 +/- 0.2 at 25ºC. Pyruvate Broth Test Procedure Expected Results of Pyruvate Broth Test Quality … Read more

o-Nitrophenyl-b-D-Galactopyranoside (ONPG) Test Principle, Procedure

Published on May 10, 2024 Written by BNO Team

o-Nitrophenyl-b-D-Galactopyranoside (ONPG) Test Overview ONPG Test Purpose ONPG Test Principle Requirements for ONPG Test ONPG broth Composition Ingredients Gms / Litre Casitose (Equivalent to Casein Peptone) 7.500 O-Nitrophenyl-β-D-galactopyranoside 1.500 Disodium hydrogen phosphate 0.350 Sodium chloride 3.750 Final pH ( at 25°C) 7.5±0.2 ONPG Test Procedure ONPG broth method ONPG disk method Discs made of ONPG-impregnated … Read more

OF (Oxidation-Fermentation) Test Principle, Purpose, Procedure

Published on May 10, 2024 Written by BNO Team

Purpose of OF Test Principle of OF Test Hugh and Leifson’s OF basal medium Composition of Hugh and Leifson’s OF basal medium Ingredients g/l Peptone (tryptone) 2.0 g Sodium chloride 5.0 g Glucose (or other carbohydrate) 10.0 g Bromthymol blue 0.03 g Agar 3.0 g Dipotassium phosphate 0.30 g Preparation Procedure of OF (Oxidation-Fermentation) Test … Read more

Novobiocin Susceptibility Test Principle, Procedure, Results

Published on May 10, 2024 Written by BNO Team

The novobiocin (antibiotic) differentiation disc can be used in the Novobiocin Susceptibility Test to help make a preliminary distinction between Staphylococcus saprophyticus and other coagulase-negative staphylococci (CoNS) in clinical (urinary) specimens.

4-Methylumbelliferyl-β-D-Glucuronide (MUG) Test Principle, Procedure, Results

Published on May 10, 2024 Written by BNO Team

Purpose Principle of MUG Test Requirements Quality control of MUG Test Using the following quality control organisms, all lot numbers of MUG Disk have been tested and found to be good. Control organisms should be tested using quality control methods that have already been set up in the lab. If there are problems with quality … Read more

X and V factor Test – Principle, Purpose, Procedure, Result

Published on May 9, 2024 Written by BNO Team

Some bacteria make substances that other bacteria need to grow. The X factor and the V factor are two such substances. The heat-stable X-factor can be protoporphyrin IX, hemin, or other iron-containing porphyrins. It can be found in red blood cells and outside of them in the blood. The heat-sensitive V-factor may be nicotinamide adenine dinucleotide (NAD) or nicotinamide adenine dinucleotide phosphate (NADP), and it is mostly found inside red blood cells. The X and V factor test or a disc test can be used to find out if a bacterium depends on its X factor or its V factor. The results can help identify the bacteria.

Hopkins Cole test (Adamkiewicz–Hopkins) Principle, Procedure, Result

Published on May 8, 2024 Written by BNO Team

Hopkin’s Cole/Adamkiewicz–Hopkins Test Definition Hopkins Cole Test also referred to as glyoxylic Acid Reaction is among the qualitative testing methods for determining the differences between different types of amino acids and proteins. The test is used to determine the presence of tryptophan, an amino acid, in proteins. Objectives of Hopkin’s Cole Test Principle of Hopkin’s … Read more