Vogel Johnson Agar Medium (USP)

Description

Vogel Johnson Agar Medium (USP) for Selective Isolation of S. aureus

Vogel Johnson Agar Medium (USP) is a highly effective and selective medium designed specifically for the isolation of Staphylococcus aureus (S. aureus) in microbiology laboratories. This medium is widely used for microbial testing, offering both precision and reliability in identifying S. aureus from various samples. The unique formula provides the ideal conditions for isolating this important pathogen, which plays a critical role in medical microbiology and food safety testing. The product’s performance ensures accuracy, helping laboratories obtain dependable results when detecting Staphylococcus aureus.

Formula and Ingredients

The Vogel Johnson Agar Medium contains a well-balanced combination of nutrients and selective agents, all of which are essential for the growth and isolation of S. aureus. These components work together to provide a stable pH environment and inhibit the growth of non-target organisms.

• Casein peptone (10.0 g/L): Supplies essential amino acids and peptides that support bacterial growth.
• Yeast Extract (5.0 g/L): Enriches the medium with vitamins and minerals, further promoting microbial growth.
• D-Mannitol (10.0 g/L): A carbohydrate source that helps in the differentiation of mannitol-fermenting organisms.
• Phenol Red (0.025 g/L): Serves as a pH indicator, allowing easy detection of acid production from mannitol fermentation.
• Dibasic Potassium Phosphate (5.0 g/L): Acts as a buffer to maintain the pH level.
• Lithium Chloride (5.0 g/L): Provides selective inhibition of organisms other than S. aureus.
• Glycine (10.0 g/L): Enhances the selectivity of the medium for S. aureus.
• Agar (16.0 g/L): Solidifies the medium, providing a surface for bacterial growth.

The final pH is 7.2 ± 0.2 at 25°C, ensuring optimal conditions for the selective isolation of S. aureus.

Easy Preparation and Directions for Use

To prepare the Vogel Johnson Agar Medium, suspend 61.0 grams of the powder in 1 liter of distilled water. Boil the mixture for 1 minute to fully dissolve the solids. Sterilize by autoclaving for 15 minutes at 121°C. After autoclaving, cool the medium to 45-50°C, then add 20 mL of sterile potassium tellurite solution (1 in 100). Thoroughly mix the solution before dispensing it into Petri dishes.

This preparation method is simple and allows laboratories to efficiently create the medium needed for accurate S. aureus isolation. Proper sterilization and cooling are key to maintaining the medium’s effectiveness and ensuring reliable microbial results.

Key Applications and Benefits

Vogel Johnson Agar Medium is designed for use in microbiology laboratories that require precise and selective identification of Staphylococcus aureus. Its formula is ideal for detecting S. aureus in a variety of settings, including medical research, clinical diagnostics, and food safety testing. By inhibiting non-target organisms, the medium ensures that S. aureus colonies are easy to identify, enhancing the efficiency of microbial testing.

Key benefits of using Vogel Johnson Agar Medium include:

• Selective isolation of S. aureus: The medium is optimized to target and grow Staphylococcus aureus, making it highly effective in identifying this pathogen.
• Clear differentiation: The inclusion of phenol red as a pH indicator allows for easy visualization of mannitol fermentation, which is characteristic of S. aureus.
• Inhibition of non-target organisms: Ingredients like lithium chloride and glycine selectively inhibit the growth of other bacteria, improving the accuracy of isolation.

By using this medium, laboratories can ensure that their microbial testing is both accurate and reliable, helping them meet the rigorous demands of microbiological analysis.

Trusted by Professionals

Microbiologists rely on Vogel Johnson Agar Medium for its proven ability to isolate S. aureus with accuracy and speed. Whether in medical or food industry laboratories, this medium helps streamline microbial identification processes, ensuring precise results every time. With a stable pH and strong selective properties, it stands out as a trusted choice for laboratories that need to reliably detect Staphylococcus aureus in their samples.

In conclusion, Vogel Johnson Agar Medium offers a comprehensive solution for isolating S. aureus, making it an essential tool in the arsenal of any microbiology lab focused on pathogen detection. visit our [United States Pharmacopeia] for more related products