MilliporeSigma
All Photos(1)

Documents

1.09293

Millipore

KOVACS′ indole reagent

for detecting microbial indole in the identification of indole-positive and indole-negative microorganisms, suitable for microbiology

Sign Into View Organizational & Contract Pricing

Synonym(s):
4-(Dimethylamino)benzaldehyde solution, Indole reagent, Kovac′s reagent, Kovac′s reagent for indoles

Quality Level

form

liquid

packaging

pkg of 100 mL

storage condition

(No metal containers. Keep the container tightly closed in a dry and well-ventilated place. Keep away from heat and sources of ignition)

technique(s)

microbe id | specific enzyme detection: suitable

color

yellow

pH

<1 (20 °C in H2O)

transition temp

flash point 36 °C

density

0.92 g/cm3 at 20 °C

application(s)

microbiology

storage temp.

2-8°C

suitability

Escherichia coli
enterovirulent E. coli (EEC) spp.

General description

Kovac′s reagent is a biochemical reagent composed of n-Butanol, hydrochloric acid, and 4-dimethylaminobenzaldehyde. It is used for the detection of indole producing microorganisms. Tryptophan is abundant in trypticalle digested peptone. Some microorganisms can cleave tryptophan to give pyruvic acid, ammonia, and indole. Indole then reacts with 4-dimethylaminobenzaldehyde to form a dark red dye. As tryptophan also gives a color reaction with 4 dimethylaminobenzaldehyde, it must be separated from the indole. This is achieved by selectively extracting indole with butanol.

Application

Kovac′s Indole reagent is used for the detection of indole producing microorganisms in food and beverages, and environmental samples. This is suitable for the identification of E. coli.

Analysis Note

Indole formation (Escherichia coli ATCC 25922 (WDCM 00013)): +
Indole formation (Proteus vulgaris ATCC 8427): +
Indole formation (Enterobacter aerogenes ATCC 13048): -
Tested in DEV-Tryptophan broth art. no. 1.10694. (after incubation 24 hrs.; 35 °C aerobic).

Other Notes

The reagent solution must be stored in the dark in the refrigerator, otherwise it may turn brown and cannot be used.

signalword

Danger

Hazard Classifications

Acute Tox. 4 Oral - Eye Dam. 1 - Flam. Liq. 3 - Met. Corr. 1 - Skin Corr. 1 - Skin Sens. 1

Storage Class

3 - Flammable liquids

wgk_germany

WGK 1

flash_point_f

96.8 °F

flash_point_c

36 °C


Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

Already Own This Product?

Documents related to the products that you have purchased in the past have been gathered in the Document Library for your convenience.

Visit the Document Library

Difficulty Finding Your Product Or Lot/Batch Number?

Product numbers are combined with Pack Sizes/Quantity when displayed on the website (example: T1503-25G). Please make sure you enter ONLY the product number in the Product Number field (example: T1503).

Example:

T1503
Product Number
-
25G
Pack Size/Quantity

Additional examples:

705578-5MG-PW

PL860-CGA/SHF-1EA

MMYOMAG-74K-13

1000309185

enter as 1.000309185)

Having trouble? Feel free to contact Technical Service for assistance.

Lot and Batch Numbers can be found on a product's label following the words 'Lot' or 'Batch'.

Aldrich Products

  • For a lot number such as TO09019TO, enter it as 09019TO (without the first two letters 'TO').

  • For a lot number with a filling-code such as 05427ES-021, enter it as 05427ES (without the filling-code '-021').

  • For a lot number with a filling-code such as STBB0728K9, enter it as STBB0728 without the filling-code 'K9'.

Not Finding What You Are Looking For?

In some cases, a COA may not be available online. If your search was unable to find the COA you can request one.

Request COA

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Contact Technical Service