Peptone Water ISO 6579 Condalab 1402

Peptone Water ISO

Peptone Water is used for the detection of Enterobacteriaceae, specifically E-Coli in water and food samples based on indole production. The tryptone provides nitrogen, vitamins, minerals, and amino acids that are essential for growth. The sodium chloride provides essential electrolytes for transport and osmotic balance. The peptone water is a good substrate to produce indole due to its high content of tryptophan. There is the ability of certain organisms to breakdown the amino acid tryptophan with indole formation is a vital property that can be used for the classification and identification of bacteria. This medium is recommended by CeNAN (National Centre for Food and Nutrition).

Preparation:

• Suspend 15 grams of the medium in one litre of distilled water
• Mix well and dissolve the mixture by heating with frequent agitation
• Boil for a minute until complete dissolution
• Dispense into containers and sterilise in autoclave for 15 minutes at 121ºC

Instructions for use:

For clinical purposes, the sample type is bacteria which is isolated from clinical samples:

• Incubate for 24 hours in aerobic conditions at 35±2 ºC
• Add 3 to 4 drops of Kovacs reagent (CL-5205)

When it comes to the indole test:

• Add 3 to 4 drops of Kovacs reagent (CL-5205) and shake gently
• If it appears red or pink in the reagent layer, this means it is a positive indication of indole
• Compare the results with the non-inoculated test tube