Technical Data
Media
Violet Red Bile Glucose Agar (Powder)
V2123-10
Microbiological Grade
Storage RT    Shipping RT
Formula per liter
Pancreactic digest of gelatin7.0g
Yeast Extract3.0g
Bile Salts#31.5g
Agar13.5g
Glucose10.0g
Sodium Chloride5.0g
Neutral Red0.03g
Crystal Violet0.002g
Total grams/liter40.0g
pH 7.4 +/- 0.2 at 25C.
Agar medium used for the detection and determination of all Enterobacteriaceae in food.

Violet Red Bile Glucose Agar is recommended for use in in the microbiological analysis of food. Violet Red Bile Glucose Agar is a selective medium which detects the growth of glucose fermenting Gram negative bacteria. The glucose fermenting bacteria lower the pH of the medium subsequently causing their colonies to look red (neutral red dye) and to precipitate the bile salts. Crystal violet and bile salts inhibit the growth of Gram positive micoorganisms.


Mix 40gram of medium powder in one liter distilled water until evenly dispersed. Heat with repeated stirring and boil for two minutes. DO NOT AUTOCLAVE. Cool to 40-45C and dispence 15-20ml into 100mm Petri dishes containing inoculum. After solidifiction of the inoculated medium, evenly add a cover of 4ml of the cooled (45C) agar medium.

Quality Control Specifications: 1. The powder is homogeneous, free-flowing and light reddish-beige 2. Visually the prepared medium is clear to slightly hazy and reddish purple. 3. Expected cultural response after 18-24 hours at 35C.

Organism Result Enterobacter aerogenes ATCC 13048 Growth, Red colonies Escherichia coli ATCC 25922 Growth, Red colonies Salmonella typhimurium ATCC 14028 Growth, Red colonies Staphylococcus aureus ATCC 25923 Growth Inhibited :

Storage: Store the sealed bottle of dehydrated medium at 2-30C. Once opened and recapped, place the container in a low humidity environment at the same storage temperature. Protect from moisture and light. Dispose of dehydrated medium if not free-flowing or if the color has changed from the original light-pinkish beige.


Important Note: This product as supplied is intended for research use only, not for use in human, therapeutic or diagnostic applications without the expressed written authorization of United States Biological.