Liofilchem Yersinia PSB Broth

Liofilchem Yersinia PSB Broth is a selective liquid medium formulated for the enrichment of Yersinia enterocolitica from food, water, and environmental samples, adhering to ISO 10273 guidelines. It is used in microbiological analysis to isolate and identify pathogenic Yersinia enterocolitica in suspected samples.

Key Features:

1. Selective Properties:
   • Incorporates bile salts to inhibit Gram-positive bacteria, ensuring selective enrichment of Yersinia enterocolitica.
2. Versatility:
   • Suitable for applications in food safety testing, water quality analysis, and environmental monitoring.
3. ISO Compliance:
   • Conforms to ISO 10273 for reliable and standardized detection of presumptive pathogenic Yersinia enterocolitica.
4. Optimized Growth Conditions:
   • Includes phosphates for buffering, sorbitol as a fermentable carbohydrate, and enzymatic digest of casein to support microbial growth.

Composition (Per Liter):

Final pH: 7.6 ± 0.2 at 25°C.

Preparation Instructions:

1. Suspend 31 g of powder in 1 liter of distilled or deionized water.
2. Heat to boiling while stirring until completely dissolved.
3. Dispense into appropriate containers.
4. Sterilize at 121°C for 15 minutes.

Testing Procedure:

1. Sample Preparation:
   • Add the test sample to Yersinia PSB Broth in a 1:10 dilution and homogenize for 2 minutes.
2. Incubation:
   • Incubate the broth at 25 ± 1°C for 3-5 days.
3. Isolation:
   • Subculture the enriched broth onto Yersinia Selective Agar (CIN) (ref. 620111).
   • Perform an additional step by adding 0.5 mL of the PSB culture to 4.5 mL of potassium hydroxide solution, mixing, and inoculating another CIN plate.
4. Incubation of Plates:
   • Incubate plates at 30 ± 1°C for 18-24 hours and examine for suspect colonies.

Result Interpretation:

• Turbidity in the broth indicates microbial growth.
• Suspect colonies on CIN Agar appear as red “bull’s-eye” colonies with a transparent border.
• Final confirmation of Yersinia enterocolitica is achieved using biochemical tests or pathogenicity tests.

Applications:

1. Food and Beverage Testing:
   • Detect contamination in raw and processed food.
2. Water Quality Analysis:
   • Analyze water samples for pathogenic Yersinia enterocolitica.
3. Environmental Monitoring:
   • Assess environmental samples for contamination in clinical or industrial settings.

Appearance:

• Dehydrated Medium: Free-flowing, homogeneous, beige.
• Prepared Medium: Clear, light amber.

Storage and Shelf Life:

• Dehydrated Medium:
  • Store at 10-30°C in a dry, sealed container.
  • Shelf life: 4 years.
• Prepared Medium:
  • Store at 2-8°C, protected from light.

Quality Control:

Precautions:

1. Hazardous Content:
   • Contains bile salts and is classified as hazardous. Refer to the Safety Data Sheet (SDS) for handling instructions.
2. Professional Use Only:
   • Must be used by trained microbiology professionals in a controlled laboratory environment.
3. Avoid Contamination:
   • Use aseptic techniques during preparation and testing.

Disposal:

• Dispose of waste as per national and local regulations.

Packaging:

References:

1. ISO 10273:2003. Microbiology of food and animal feeding stuffs – Horizontal method for the detection of presumptive pathogenic Yersinia enterocolitica.
2. Weagant, S.D., and P. Feng. Bacteriological Analytical Manual: Yersinia enterocolitica. U.S. Food and Drug Administration.
3. Devenish, J.A., and D.A. Schieman. Identification of Yersinia enterocolitica from food enrichments. Can. J. Microbiol. 27:937-941.

Liofilchem Yersinia PSB Broth provides a selective and efficient liquid medium for isolating and enriching Yersinia enterocolitica. With its adherence to ISO 10273, it is an essential tool for food safety, water quality, and environmental monitoring applications. The medium’s selectivity and compliance with international standards make it reliable for accurate detection and enumeration.