Part of Thermo Fisher Scientific

Thermo Scentific
 
 
 

Dehydrated Culture Media

printer friendly version

BUFFERED PEPTONE WATER (ISO)

CODE: CM1049

Typical Formula*

gm/litre

Enzymatic digest of casein

10.0

Sodium chloride

5.0

Disodium hydrogen phosphate (anhydrous)

3.5

Potassium dihydrogen phosphate
1.5
pH 7.0 ± 0.2 @ 25°C  
* Adjusted as required to meet performance standards
equivalent to 9.0 g of disodium hydrogen phosphate dodecahydrate

Directions
Add 20.0g of Buffered Peptone Water (ISO) to 1 litre of distilled water. Mix well and distribute into final containers. Sterilise by autoclaving at 121°C for 15 minutes.

Description
Buffered Peptone Water (ISO) is a non-selective pre-enrichment medium for the isolation of Salmonella species from food and associated samples. As Salmonella may be present in low numbers and/or sub-lethally injured pre-enrichment allows the cells time to repair and multiply before being introduced to selective culture, thereby improving the chances of recovery from the sample.

The medium is designed to be used prior to selective enrichment in RVS Broth CM0866 or Modified Semi-solid Rappaport-Vassiliadis (MSRV) agar (CM1128) with Novobiocin selective supplement SR0181 and MKTTn Broth CM1048 with Novobiocin Selective Supplement SR0181 according to ISO 6579:20171.

The quality control of Buffered Peptone Water (ISO) CM1049 includes testing in accordance with ISO 65791 and ISO 11133:20142.

Method of use
The sample is added to Buffered Peptone Water (ISO) at a ratio of 1:10, and incubated at 36°C ± 2°C for 16-20 hours before transfer to selective enrichment media1.

Storage conditions and Shelf life
Store the dehydrated medium at 10-30°C and use before the expiry date on the label.

Appearance
Dehydrated medium: Straw coloured, free-flowing powder
Prepared medium: Light, straw coloured solution

Quality control

Positive control

Expected results

Salmonella Typhimurium ATCC® 14028 *
WDCM 00031

Turbid growth

Salmonella Enteritidis ATCC® 13076*
WDCM 00030

Turbid growth

Negative control

 

Uninoculated medium

No change

* This organism is available as a Culti-Loop®

References
1. ISO 6579-1:2017 Microbiology of the food chain -- Horizontal method for the detection, enumeration and serotyping of Salmonella -- Part 1: Detection of Salmonella spp.
2. ISO 11133:2014 Microbiology of food, animal feed and water - Preparation, production, storage and performance testing of culture media.

 
©2001 - 2019 Oxoid Limited, All rights reserved.
Copyright, Disclaimer and Privacy Policy | Conditions of Sale | About Us | Cookies
Thermo Fisher Scientific Inc.