VIOLET RED BILE GLUCOSE AGAR

Technical Data #39-5603a / 2013.08.18

Violet Red Bile Agar is a solid medium used for the detection and isolation of enterobcateriaceae in food. Bile salts and crystal violet are the inhibitors of gram-positive microorganisms. Glucose fermenting bacteria lower the pH of the medium and change the medium to red color with precipitation of bile salts.

 


 

FORMULA
in grams per liter purified filtered water

Gelatin Peptone

7,0

Bile Salts #3

1,5

Yeast Extract

3,0

Glucose

10,0

Sodium Chloride

5,0

Neutral Red

0,03

Crystal Violet

0,002

Agar

13,5

pH 7,4 +/- 0,2 à 25º C

This approximate formula may be adjusted and/or enriched to obtain best results.


PRECAUTIONS
This medium is for laboratory use only.


STORAGE
Store dehydrated powder, in a dry place, in tightly-sealed containers at 2-25º C.


SIGN OF DETERIORATION
Media should not be used if the expiry date has passed. Do not use dehydrated media if it is caked.


DIRECTIONS
Suspend 40 g of dehydrated media in 1000 ml of purified filtered water. Heat with frequent agitation and boil for one minute. Sterilize at 121º C for 15 minutes. Cool to 45-50º C. Mix gently and dispense into sterile Petri dishes.


PROCEDURE
Prior to inoculate, the prepared media should be brought to room temperature.

  1. Directly, inoculate plate as soon as possible with specimen and streak for isolation.
  2. Incubate at 35º C for 24 hours.


QUALITY CONTROL

Results after 24 hrs at 35ºC

Organisms

ATCC

Growth

Colour

Escherichia coli

25922

+

red, bile point

Enterobacter aerogenes

13048

+

red, bile point

Salmonella typhimurium

14028

+

red, bile point

Staphylococcus aureus

25923

-

 


LIMITATIONS OF METHOD
This medium is only a part of the identification. Other tests may be required.


REFERENCES

  1. Atlas R.M., Hand book of Microbiological Media 1997 2nd, ed. CRC PRESS
  2. Mossel D.A.A., VAN DER Zee H., Hardon A.P. and van Netten P., 1986 J. Appl. Bact. 60:289-295


CATALOGUE NUMBERS

Dehydrated media 500 g QB-39-5603

 


 

 

2325, Dandurand, Suite 300 Phone Fax Internet
Montréal (Quebec) (514) 277-2558 (514) 277-4714 http://www.quelab.com
Canada H2G 1Z9 1 (800) 579-0998 1 (800) 579-8177 info@quelab.com