Lactose Peptone Broth , 250g

Description: 

Coliform bacteria are commonly used as bacterial indicator of sanitary quality of foods and water. Where it is claimed that drinking water has been processed for safety, the finding of such o rganism demonstrates a failure of the process. It is a valuable bacterial indicator for determining the extent of faecal contamination of recreational surface waters or drinking water (1). Coliforms are defined as rod -shaped gram-negative organisms, which ferment lactose with the production of acid and gas when incubated at 35°C. Lactose Peptone Broth was originally described in German Standard Methods and German Drinking Water Regulations (2) as a non -selective enrichment and detection medium for Escherichia coli and other coliforms in water specimens.

German standards suggest the use of MPN technique with 0.1, 1.0 and 10 ml of sample and an incubation at 36 ± 1°C for 44 ± 4 hours. Depending upon the sample volume the medium can be either used as single strength or triple strength. Tubes that change to yellow and eventual gas production in Durhams tubes are considered positive. Casein enzymic hydrolysate and papaic digest of soyabean meal provide all the essential nitrogenous growth nutrients. Lactose is the fermentable sugar. Lactose fermentation and gas production form the basis for the presumptive coliform identification. Sodium chloride maintains osmotic equilibrium. Bromocresol purple is the pH indicator of the medium, which turns yellow as a result of acid production from the fermentation of lactose. 

Specification: 

250g