1. The document describes three bacterial tests - the Indole test, Lysine Decarboxylase test, and Mannitol Fermentation test - that were performed to identify E. coli bacteria.
2. The Indole test detects the production of indole from tryptophan, the Lysine Decarboxylase test examines an enzyme's ability to break down lysine, and the Mannitol Fermentation test observes acid production from fermenting mannitol.
3. These tests can help differentiate between bacterial species like distinguishing E. coli from other Proteus or Klebsiella species.
Most probable number or multiple tube fermentation techniqueSamsuDeen12
multiple tube fermentation or most probable number is a microbiological technique used to check the portability of water. microbial analysis of water is determined, and distinguished between faecal and non faecal contaminated water.
Endotoxin Testing is performed to ensure that injectable preparations and medical devices are free from pyrogens and safe for human use.
Pyrogens constitute a heterogeneous group of fever causing substances which comprise both microbial and non-microbial substances. The most potent and most widely known are the endotoxins or lipopolysaccharides (LPS), which are cell wall components of gram-negative bacteria. Gram-positive bacteria are also sources of pyrogens, in particular lipoteichoic acid (LTA), as are particles from yeasts and viruses. Non-microbial pyrogens often emanate from production environments. Small particles of packaging materials are a typical example.
The inhibition of growth under standardized conditions may be utilized for demonstrating the therapeutic efficacy of antibiotics.
Any subtle change in the antibiotic molecule which may not be detected by chemical methods will be revealed by a change in the antimicrobial activity and hence microbiological assays are very useful for resolving doubts regarding possible change in potency of antibiotics and their preparations.
principle;
The microbiological assay is based upon a comparison of the inhibition of growth of micro-organisms by measured concentration of the antibiotics to be examined with that produced by known concentrations of a standard preparation of the antibiotic having a known activity.
Two general method are usually employed:-
The cylinder-plate (or cup-plate) method.
The turbidimetric (or tube assay) method.
5.1.3. Efficacy of antimicrobial preservation (EP 5.0)Guide_Consulting
Salah Satu Referensi Yang Digunakan Dalam One Day Seminar "Preservative Effectiveness Validation" 04 Desember 2014.
Detail : info@traininglaboratorium.com
2.6.12. microbiological examination of non sterile products (total viable aer...Guide_Consulting
Salah Satu Referensi Yang Digunakan Dalam One Day Seminar "Preservative Effectiveness Validation"
04 Desember 2014. Bogor
Detail : info@traininglaboratorium.com
In-House Microbial Isolates in Compendial Testing: Regulatory RequirementsRobert Westney
This presentation provides an overview of the current regulatory expectations for the use of in-house microbial isolates in compendial testing. It reviews regulatory, compendial and industry references on the topic. Importantly, it also provides a strategy for selection of these isolates.
The Bacterial Endotoxin Test BET is a test to quantify Endotoxin from ‘Gram negative bacteria using ‘amoebocyte lysate' extracted from ‘Limulus polyphemus or Tachypleus tridentatus' i.e. horseshoe crab. Three techniques are used for the confirmation of endotoxins, those are the gel clot technique, the turbidimetric technique, and the chromogenic technique. Endotoxins are toxic complexes which is invariably associated with the cell wall of the Gram negative bacteria irrespective of bacterial pathogenicity. Endotoxins are rarely fatal, but they cause fever and hence Endotoxin carrying bacteria are known as ‘Pyrogen'. The test can be done by any of these three techniques. Among all, the gel clot method is chosen to be superior. The test is carried out in a manner to avoid endotoxins contamination. Mostly bacterial Endotoxin test are performed for the inject able pharmaceutical products, e.g. SWFI Sterile Water for Injection , Normal Saline Sodium Chloride Sterile and other injections like Amikacin sulphate, Ascorbic acid, etc. Endotoxin had been authenticated as inflammatory agent, onset clinical diabetes, obesity, nausea, vomiting, diarrhea, fever, etc. Endotoxins are thus very necessary to get removed out from the inject able pharmaceutical products. Faiz Hashmi | Ankush Thakur ""Bacterial Endotoxin Test by Gel-Clot Method"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-3 , April 2019, URL: https://www.ijtsrd.com/papers/ijtsrd22945.pdf
Paper URL: https://www.ijtsrd.com/pharmacy/biotechnology-/22945/bacterial-endotoxin-test-by-gel-clot-method/faiz-hashmi
Microbiological assay-Principles and methods of different microbiological assay.someshwar mankar
Principles and methods of different microbiological assay. Methods for standardization of
antibiotics, vitamins and amino acids. Assessment of a new antibiotic.
Most probable number or multiple tube fermentation techniqueSamsuDeen12
multiple tube fermentation or most probable number is a microbiological technique used to check the portability of water. microbial analysis of water is determined, and distinguished between faecal and non faecal contaminated water.
Endotoxin Testing is performed to ensure that injectable preparations and medical devices are free from pyrogens and safe for human use.
Pyrogens constitute a heterogeneous group of fever causing substances which comprise both microbial and non-microbial substances. The most potent and most widely known are the endotoxins or lipopolysaccharides (LPS), which are cell wall components of gram-negative bacteria. Gram-positive bacteria are also sources of pyrogens, in particular lipoteichoic acid (LTA), as are particles from yeasts and viruses. Non-microbial pyrogens often emanate from production environments. Small particles of packaging materials are a typical example.
The inhibition of growth under standardized conditions may be utilized for demonstrating the therapeutic efficacy of antibiotics.
Any subtle change in the antibiotic molecule which may not be detected by chemical methods will be revealed by a change in the antimicrobial activity and hence microbiological assays are very useful for resolving doubts regarding possible change in potency of antibiotics and their preparations.
principle;
The microbiological assay is based upon a comparison of the inhibition of growth of micro-organisms by measured concentration of the antibiotics to be examined with that produced by known concentrations of a standard preparation of the antibiotic having a known activity.
Two general method are usually employed:-
The cylinder-plate (or cup-plate) method.
The turbidimetric (or tube assay) method.
5.1.3. Efficacy of antimicrobial preservation (EP 5.0)Guide_Consulting
Salah Satu Referensi Yang Digunakan Dalam One Day Seminar "Preservative Effectiveness Validation" 04 Desember 2014.
Detail : info@traininglaboratorium.com
2.6.12. microbiological examination of non sterile products (total viable aer...Guide_Consulting
Salah Satu Referensi Yang Digunakan Dalam One Day Seminar "Preservative Effectiveness Validation"
04 Desember 2014. Bogor
Detail : info@traininglaboratorium.com
In-House Microbial Isolates in Compendial Testing: Regulatory RequirementsRobert Westney
This presentation provides an overview of the current regulatory expectations for the use of in-house microbial isolates in compendial testing. It reviews regulatory, compendial and industry references on the topic. Importantly, it also provides a strategy for selection of these isolates.
The Bacterial Endotoxin Test BET is a test to quantify Endotoxin from ‘Gram negative bacteria using ‘amoebocyte lysate' extracted from ‘Limulus polyphemus or Tachypleus tridentatus' i.e. horseshoe crab. Three techniques are used for the confirmation of endotoxins, those are the gel clot technique, the turbidimetric technique, and the chromogenic technique. Endotoxins are toxic complexes which is invariably associated with the cell wall of the Gram negative bacteria irrespective of bacterial pathogenicity. Endotoxins are rarely fatal, but they cause fever and hence Endotoxin carrying bacteria are known as ‘Pyrogen'. The test can be done by any of these three techniques. Among all, the gel clot method is chosen to be superior. The test is carried out in a manner to avoid endotoxins contamination. Mostly bacterial Endotoxin test are performed for the inject able pharmaceutical products, e.g. SWFI Sterile Water for Injection , Normal Saline Sodium Chloride Sterile and other injections like Amikacin sulphate, Ascorbic acid, etc. Endotoxin had been authenticated as inflammatory agent, onset clinical diabetes, obesity, nausea, vomiting, diarrhea, fever, etc. Endotoxins are thus very necessary to get removed out from the inject able pharmaceutical products. Faiz Hashmi | Ankush Thakur ""Bacterial Endotoxin Test by Gel-Clot Method"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-3 , April 2019, URL: https://www.ijtsrd.com/papers/ijtsrd22945.pdf
Paper URL: https://www.ijtsrd.com/pharmacy/biotechnology-/22945/bacterial-endotoxin-test-by-gel-clot-method/faiz-hashmi
Microbiological assay-Principles and methods of different microbiological assay.someshwar mankar
Principles and methods of different microbiological assay. Methods for standardization of
antibiotics, vitamins and amino acids. Assessment of a new antibiotic.
ISOLATION AND IDENTIFICATION OF NLF BACTERIA IN VARIOUS SAMPLES.Daisy Saini
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TESTING OF DISINFECTANT CLASSES OF DISINFECTANTS METHOD FOR TESTING DISINFEC...VeerendraMaravi
HISTORY
INTRODUCTION
CLASSES OF DISINFECTANTS
METHOD FOR TESTING DISINFECTANTS
CARRIER TEST
CAPACITY TEST
SUSPENSION TESTS
PRACTICAL TEST
IN USE TEST
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TEST ORGANISMS
Isolation and Molecular Characterization of Pullulanase Producing Bacillus St...YogeshIJTSRD
Pullulanase is an extracellular carbohydrase responsible for the hydrolysis of pullulan and amylopectin toproduce maltotriose. The product maltotriose is used in detergent industry, bakery industry and in the production of biotechnological products. In the present investigation pullulanase producing bacillus species were isolated and characterized using different biochemical and molecular methodologies. The isolates were identified as Bacillus cereus and Bacillus thuringiensis respectively.. The pullulanase acivity was higher in Bacillus cereus, 0.62U ml than B. thuringiensis, 0.53 U ml. This research reveals that pullulanase enzyme production from these Bacillus species shows great promise for use in industrial processes. Nwozor, N. C | Ogbo, F. C "Isolation and Molecular Characterization of Pullulanase Producing Bacillus Strains" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-5 , August 2021, URL: https://www.ijtsrd.com/papers/ijtsrd45051.pdf Paper URL: https://www.ijtsrd.com/biological-science/microbiology/45051/isolation-and-molecular-characterization-of-pullulanase-producing-bacillus-strains/nwozor-n-c
Detection of Alpha-Amylase Activity from Soil Bacteriaiosrjce
Alpha-amylase is one of the industrial enzymes that hydrolyze starch molecules into polymers
composed of glucose units. The enzyme has potential application in a wide number of industrial processes such
as food, textile, paper, detergent, fermentation and pharmaceutical industries. Alpha-amylase can be produced
by microorganisms, plants or animals.
Aim: The aim of this study is to detect the activity of alpha-amylase from bacteria isolated from soil
environment.
Method: Soil samples were inoculated onto the media that are rich in nutrient that favour the growth of the
bacteria and incubated for 24 hours at 37oC after which the bacterial growth was detected in form of colonies.
In this study, bacterial species belonging to the genus Bacillus were identified through phylogenetic analysis
using 16s-ribosomal RNA sequencing for detection of the enzymatic activity. Effects of pH and temperature on
the enzymatic activity were observed using DNS activity assay method.
Results: Positive response to alpha-amylase activity by the soil bacteria was observed by the formation of clear
zone of inhibition shown by the colonies on the petri plates.
Conclusions: The optimal pH and temperature activities showed that the bacteria exhibit enzymatic activity at
mesophilic temperature and acidophilic or alkalophilic pH.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
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Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
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Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
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11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
The ability to recreate computational results with minimal effort and actionable metrics provides a solid foundation for scientific research and software development. When people can replicate an analysis at the touch of a button using open-source software, open data, and methods to assess and compare proposals, it significantly eases verification of results, engagement with a diverse range of contributors, and progress. However, we have yet to fully achieve this; there are still many sociotechnical frictions.
Inspired by David Donoho's vision, this talk aims to revisit the three crucial pillars of frictionless reproducibility (data sharing, code sharing, and competitive challenges) with the perspective of deep software variability.
Our observation is that multiple layers — hardware, operating systems, third-party libraries, software versions, input data, compile-time options, and parameters — are subject to variability that exacerbates frictions but is also essential for achieving robust, generalizable results and fostering innovation. I will first review the literature, providing evidence of how the complex variability interactions across these layers affect qualitative and quantitative software properties, thereby complicating the reproduction and replication of scientific studies in various fields.
I will then present some software engineering and AI techniques that can support the strategic exploration of variability spaces. These include the use of abstractions and models (e.g., feature models), sampling strategies (e.g., uniform, random), cost-effective measurements (e.g., incremental build of software configurations), and dimensionality reduction methods (e.g., transfer learning, feature selection, software debloating).
I will finally argue that deep variability is both the problem and solution of frictionless reproducibility, calling the software science community to develop new methods and tools to manage variability and foster reproducibility in software systems.
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at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
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infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
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Phenomics assisted breeding in crop improvementIshaGoswami9
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change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
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the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
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Mudde & Rovira Kaltwasser. - Populism - a very short introduction [2017].pdf
bacterial test
1. MAHATMAGANDHI CENTRALUNIVERSITY
Assignment- E.COLI BACTERIAL TEST
1.INDOL TEST
2.LYSINE DECARBOXYLASE TEST
3.MENITOL FERMENTATIONTEST
Session-2019-21
Departmentof Biotechnology
M.Sc (Biotechnology) Semester-4
NAME-MANISHKUMAR
ROLL.NO-MGCU2019BIOT4007
SUBJECT-MEDICAL BIOTECHNOLOGY
SUBMITTED TO
DRSAURABH SINGHRATHORE
2. 1.Indole Test
Thistestdemonstrate the abilityof certainbacteriatodecompose the aminoacidtryptophanetoindole,
whichaccumulatesinthe medium.
Indole productiontestisimportantinthe identificationof Enterobacteria.
Most strainsof E. coli,P.vulgaris,P.rettgeri,M.morgani and Providenciaspeciesbreakdownthe amino
acid tryptophanwiththe release of indole.
Thisis performedbyachain of a numberof differentintracellularenzymes,asystemgenerallyreferred
to as “tryptophanase.”
It is usedas part of the IMViCprocedures,atestsdesignedtodistinguishamongmembersof the family
Enterobacteriaceae.
A variationonthistestusingEhrlich’sreagent(usingethyl alcohol inplace of isoamylalcohol,developed
by Paul Ehrlich) isusedwhenperformingthe testonnon-fermentersandanaerobes.
Principle of Indole Test
Tryptophan is an amino acid that can undergo deamination and hydrolysis by bacteria that
express tryptophanase enzyme.
Indole is generated by reductive deamination from tryptophan via the intermediate
molecule indolepyruvic acid.
Tryptophanase catalyzes the deamination reaction, during which the amine (-NH2) group of
the tryptophan molecule is removed.
Final products of the reaction are indole, pyruvic acid, ammonium (NH4+) and energy.
Pyridoxal phosphate is required as a coenzyme.
When indole is combined with Kovac’s Reagent (which contains hydrochloric acid and p-
dimethylaminobenzaldehydein amyl alcohol) the solution turns from yellow to cherry red.
Because amyl alcohol is not water soluble, the red coloration will form in an oily layer at the
top of the broth.
In the spot test, indole combines, in the filter paper matrix, at an acid pH with p-
Dimethylaminocinnamaldehyde (DMACA) to produce a blue to blue-green compound.
3. Indole Spot Reagent has been reported to be useful in detecting indole production by members
of the family Enterobacteriaceaeand certain anaerobicspecies.
Reagents Used in Indole Test
Ingredients per liter:*
Indole Spot Reagent:
p-Dimethylaminocinnamaldehyde(DMACA) 10.0 gm
Hydrochloric Acid, 37% 100.0 ml
Deionized Water 900.0 ml
Indole Kovacs Reagent:
p-Dimethylaminobenzaldehyde 50.0 gm
Hydrochloric Acid, 37% 250.0 ml
Amyl Alcohol 750.0 ml
* Adjusted and/or supplemented as required to meet performance criteria
Indole Spot Reagent (DMACA) Procedure
1. Place several drops of Indole Spot Reagent on a piece of filter paper.
2. With an inoculating loop or wooden applicator stick, pick a portion of an 18-24 hour
isolated colony from a non-selective media and rub it onto the reagent saturated area of
the filter paper.
3. Examine immediately
Result Interpretation of Indole Test
Positive: Formation of a pink to red color (“cherry-red ring”) in the reagent layer on top of the
medium within seconds of adding the reagent.
Examples: Aeromonas hydrophila, Aeromonas punctata, Bacillus
alvei,Edwardsiella sp., Escherichia coli, Flavobacterium sp., Haemophilus influenzae, Klebsiella
4. oxytoca, Proteus sp. (not P. mirabilis and P. penneri), Plesiomonas shigelloides,Pasteurella
multocida, Pasteurella pneumotropica, Enterococcus faecalis, and Vibrio sp.
Negative: No color change even after the addition of appropriate reagent.
Examples: Actinobacillus spp., Aeromonas salmonicida, Alcaligenes sp.,
most Bacillus sp., Bordetella sp., Enterobacter sp., Lactobacillus spp., most Haemophilus sp.,
most Klebsiella sp., Neisseria sp., Pasteurella haemolytica, Pasteurella ureae, Proteus mirabilis, P.
penneri, Pseudomonas sp.,Salmonella sp., Serratia sp., Yersinia sp.
Uses of Indole Test
1. To differentiate Proteus mirabilis (indole negative) from all other Proteus species (indole
positive).
2. To differentiate Klebssiella pneumoniae (indole negative) from Klebsiella oxytoca (indole
positive).
3. To differentiate Citrobacter freundii (indole negative) from Citrobacter koseri (indole
positive).
Limitations of Indole Test
1. Indole tests may be used as an aid in the identification and differentiation of gram-
positive and gram-negative organisms. Additional biochemical testing using pure
cultures is recommended for complete identification.
2. The tube test is a more sensitive method of detecting indole than the spot test.
3. When performing a spot test, Kovacs Indole Reagent may be used as a substitute for the
spot test reagent. However, Kovacs Indole Reagent, when used as the spot test reagent,
is less sensitive in detecting indole than the Indole Spot Reagent (DMACA).
4. Kovacs Indole Reagent is not recommended for use with anaerobic bacteria. The Indole
Spot Reagent (DMACA) is suitable for anaerobeuse.
5. Since peptones have been shown to vary with regard to their suitability for use with
indole testing, media selected for indole determination should be tested with known
positive and negative organisms to insure suitability.
2.LYSINE DECARBOXYLASE TEST
Decarboxylase test is a biochemical test performed to differentiate
members of Enterobacteriaceae on the basis of their ability to produce
the enzyme decarboxylase.
5. Decarboxylation occurs in the presence of a decarboxylase
enzyme that catalyzes the breaking of the bond that binds the
carboxylic group to the rest of the amino acid.
Objectives of Decarboxylase Test
To test the ability of an organism to produce a decarboxylase
enzyme.
To differentiate the members of the Enterobacteriaceae family on
the basis of their ability to produce decarboxylase enzyme.
PRINCIPLEOFDECARBOXYLASE
Arginine, lysine, and ornithine decarboxylase media are used to detect an
organism’s ability to decarboxylate or hydrolyze an amino acid, forming an amine
that produces an alkaline Ph
The decarboxylation of lysine yields cadaverine, decarboxylation of ornithine
produces putrescine, and decarboxylation of arginine results in agmatine, which is
hydrolyzed by a Dihydrolase to form putrescine
Microorganisms Tested
Enteric Gram-negative rods and Vibrio, Plesiomonas, and Aeromonas for
identification to the species level
Probable Stenotrophomonas and Burkholderia (lysine and arginine)
Fluorescent Pseudomonas (arginine)
Coagulase-negative staphylococci(ornithine)
Viridans group streptococci (arginine)
Miscellaneous non-glucose-fermenting, Gram-negative rods (arginine)
Spreading indole-negative Proteus (ornithine)
Procedure of decarboxylase test
A. Preparation of the media
B. Decarboxylase test
1.For Glucose-Fermenting Organisms
2.Glucose-Nonfermenting Organisms
Uses of decarboxylase test
Decarboxylase test is used to differentiate the members of the
Enterobacteriaceae family with closely related physiological
characteristics.
Arginine decarboxylase is useful in the identification
of Enterococcus to the species level; Enterococcus
6. faecalis and Enterococcus faecium are arginine positive
but, Enterococcus avium is arginine negative.
Lysine decarboxylase is used to differentiate
between Salmonella (+) and Shigella (-).
Limitation of decarboxylase test
Mineral oil or a similar barrier to gas release must be applied to
the surface of each inoculated broth medium. Oil on the surface
reduces the possibility of an alkaline shift occurring in the medium
due to oxidation.
Result interpretation should not be made prior to 18 to 24 hours of
incubation. Earlier interpretation may lead to erroneous results.
Glucose fermentation occurs within the first 10 to 12 hours of
incubation. The acidic environment from fermentation is necessary
for the production of decarboxylase
3.Mannitol fermentationtest
The purpose is to see if the microbe can ferment the carbohydrate (sugar) mannitol as a
carbon source.
If mannitol is fermented to produce acid end products, the pH of the medium will drop.
Principle
The principle of carbohydrate fermentation states that the action of organism on a carbohydrate
substrate results in acidification of the medium, detected by a pH indicator dye. Carbohydrate
fermentation is the process microorganisms use to produce energy. Most microorganisms
convert glucose to pyruvate during glycolysis; however, some organisms use alternate pathways.
A fermentation medium consists of a basal medium containing a single carbohydrate (glucose,
lactose, sucrose, mannitol etc.) for fermentation. However, the medium also contains various pH
indicators. In addition to a pH indicator to detect the production of acid from fermentation, a
Durham tube is placed in each tube to capture gas produced by metabolism. The carbohydrate
fermentation patterns shown by different organisms are useful in differentiating among bacterial
groups or species.
Media
The purple broth consists of peptone with the pH indicator bromcresol purple. Specific
carbohydrates are added in a concentration of 0.5-1%.
Method
1. Allow medium to warm to room temperature prior to inoculation.
7. 2. Inoculate the Purple Broth (with carbohydrate of choice) with isolated colonies from an
18-24 hour pure culture of the organism.
3. Inoculate a control tube of Purple Broth Base in parallel with the carbohydrate based
media.
4. Incubate inoculated media aerobically at 35-37ºC. for 3-5 days.
Note: Increased incubation up to 30 days may be necessary for some microorganisms.
5.Observe daily for development of a yellow color in the medium.
Result Interpretation
Positive: The development of a yellow color in the medium is indicative of a positive
carbohydrate fermentation reaction.
Negative: Lack of yellow color development is indicativeof a negative carbohydrate
fermentation reaction.
Gas formation is indicated by the appearance of gas bubbles in the Durham tube.
Uses
It is recommended for the determination of fermentation reactions of microorganisms,
especially enteric bacilli and Enterococcus
They are used primarily for the differentiation and presumptive identification of gram-
negative enteric bacilli basedon patterns of carbohydrate fermentation.
Limitations
It is recommended that biochemical, immunological, molecular, or mass spectrometry
testing be performed on colonies from pure culture for complete identification.
It may be necessary to invert the tube prior to inoculation if bubbles are trapped in the
durham tube. Trapped bubbles that are not released may lead to false-positiveresults
REFERENCE
https://microbiologyinfo.com/indole-test-principle-reagents-procedure-result-interpretation-and-
limitations/#:~:text=Principle%20of%20Indole%20Test,bacteria%20that%20express%20tryptop
hanase%20enz
https://microbiologyinfo.com/fermentation-test/
https://microbenotes.com/decarboxylase-test-principle-procedure-and-result-
interpretation/#:~:text=produce%20decarboxylase%20enzyme.-
,Principle%20of%20Decarboxylase%20Test,that%20producesSS