Granular Culture Media

Usages?
For determination of faecal coliforms and E. coli confirmatory testing.
 
Principle:
Tryptone provides carbon and nitrogen sources; the 3rd bile suppresses gram-positive bacteria, especially against Gram-positive bacteria and faecal streptococci; lactose is fermentable sugars; potassium hydrogen phosphate and potassium dihydrogen phosphate as a buffer; sodium chloride maintains osmotic equilibrium.

Packaging Size:
250g/bottle
 
Formulation (per litre):
Tryptone: 20.0g
The 3rd bile: 1.5g
Lactose: 5.0g
Dipotassium hydrogen: 4.0g
Potassium dihydrogen phosphate: 1.5g
Sodium chloride:5.0g
Final pH 6.9 ± 0.2
 
How to use:

1. Suspend 37g in 1 L of distilled water or deionized water, stirring heated to boiling until completely dissolved, packed in with a small test tube inverted tube, and autoclave at 121 ? for 15min, leave to cool to room temperature and set aside.
2. Diluted and treated sample.

 
Storage: Store in a dark, cool and dry place, tighten the cap immediately after use. Storage period of three years.
 
References:

• 1. GB / T 4789.38-2008 People's Republic of China national standards for food safety standards of food hygiene microbiological testing E. coli count
• 2. GB / T 4789.39-2008 People's Republic of China national standards for food safety standards of food hygiene microbiological examination of faecal coliform count
• 3. SN 0169-92 People's Republic of China Import and Export Commodity Inspection industry-standard export food coliform, faecal coliform and E. coli test methods
• 4. ISO7251-2005 microbiology of food and animal feeding stuffs ----- Horizontal method for the detection and enumeration of presumptive Escherichia coli ---- Most probable number technique