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| Product Name | Violet Red Bile Glucose Agar (VRBG) (Ph. Eur.) (ISO 21528) (Contact Plate) |
| Intended Use | For microbiology testing |
| Formulation | Agar medium containing peptone, bile salts, glucose, and violet red dye |
| Appearance | Reddish purple agar |
| PH Range | 7.0 - 7.2 |
| Incubation Temperature | 35-37°C |
| Test Results | Selective for coliform bacteria which produce pink to red colonies with a metallic sheen, lactose fermenting organisms produce yellow colonies |
| Shelf Life | Store between 2-8°C and use before expiration date on the label |
| Regulatory Approval | Complies with European Pharmacopoeia standards |
| Quality Control | Regular performance testing recommended to ensure quality and consistency |
| Recommended Storage | Store in a dry place, protect from light |
FAQ
What is Violet Red Bile Glucose Agar (VRBG) and what is its purpose in microbiology?
VRBG is a selective and differential medium used for the detection and enumeration of Enterobacteriaceae in various samples, particularly in the food and water industries.
How does VRBG work to selectively isolate Enterobacteriaceae?
VRBG contains bile salts and crystal violet, which inhibit the growth of Gram-positive bacteria and most Gram-negative bacteria other than Enterobacteriaceae. This selective inhibition allows for the growth of Enterobacteriaceae on the agar plate.
What makes VRBG a differential medium?
VRBG contains glucose and the pH indicator neutral red. Fermentation of glucose by Enterobacteriaceae produces acid and lowers the pH of the medium, causing the colonies to appear red. Non-fermenting bacteria will not produce acid, and their colonies will appear colorless or very pale pink.
How can VRBG plates be used for contact plate sampling in microbiology?
VRBG plates can be used as contact plates by pressing the agar side onto the surface to be sampled. This technique allows for efficient collection of microbial contaminants present on surfaces, such as countertops, equipment, or workbenches.
What are the advantages of using VRBG for microbiological testing?
VRBG provides a reliable and accurate method for the detection and enumeration of Enterobacteriaceae in various samples. The selective and differential properties of VRBG make it a valuable tool for quality control and monitoring of hygiene in food and water industries.
VRBG is a selective and differential medium used for the detection and enumeration of Enterobacteriaceae in various samples, particularly in the food and water industries.
How does VRBG work to selectively isolate Enterobacteriaceae?
VRBG contains bile salts and crystal violet, which inhibit the growth of Gram-positive bacteria and most Gram-negative bacteria other than Enterobacteriaceae. This selective inhibition allows for the growth of Enterobacteriaceae on the agar plate.
What makes VRBG a differential medium?
VRBG contains glucose and the pH indicator neutral red. Fermentation of glucose by Enterobacteriaceae produces acid and lowers the pH of the medium, causing the colonies to appear red. Non-fermenting bacteria will not produce acid, and their colonies will appear colorless or very pale pink.
How can VRBG plates be used for contact plate sampling in microbiology?
VRBG plates can be used as contact plates by pressing the agar side onto the surface to be sampled. This technique allows for efficient collection of microbial contaminants present on surfaces, such as countertops, equipment, or workbenches.
What are the advantages of using VRBG for microbiological testing?
VRBG provides a reliable and accurate method for the detection and enumeration of Enterobacteriaceae in various samples. The selective and differential properties of VRBG make it a valuable tool for quality control and monitoring of hygiene in food and water industries.
