BacterTube™ Selenite Broth

Ready-to-use liquid medium used for the enrichment and isolation of Salmonella spp. from clinical and food samples
Code: 08016
Packaging: 50 tubes/ box or as per customer request.
Storage Conditions: 2–8°C.
Transportation: Ambient temperature.
Shelf Life: 6 months from the date of manufacture.

INTENDED USE

BacterTube™ Selenite Broth is a selective enrichment medium used for the isolation of Salmonella spp. from faeces, urine, other pathological materials or food sample.

PRINCIPLES

BacterTube™ Selenite Broth contains sodium hydrogen selenite, which selectively inhibits the growth of many Gram-positive and some Gram-negative bacteria while allowing the enrichment of Salmonella spp. Peptone provides essential nutrients for bacterial growth, while lactose helps in reducing the toxicity of selenite. The selective properties of selenite enable the preferential growth of Salmonella over competing microorganisms.

Allow the medium tube to stabilize at room temperature.
Add 1g of the sample or 1ml of the solution into the tube, or directly insert the sampling swab into the tube containing the medium.
Completely dissolve the mixture in the tube.
Incubate under aerobic conditions for 18 – 24 hours at 35 – 37°C.
After incubation, transfer 1 – 2 drops from the broth onto a selective medium (MacConkey) to isolate bacterial colonies.
Continue incubating at 35 – 37°C

Notes:

Escherichia coli and Proteus species are not indefinitely inhibited. If the initial concentration of these microorganisms is high, it is best to perform subculturing on solid agar medium after 6 hours of incubation in selenite broth. Do not incubate for more than 24 hours, as the effectiveness of selenite decreases after 6-12 hours.

RESULTS

Salmonella will be enriched in the broth and can be further isolated on selective agar plates.
Non-target organisms may be inhibited or present in reduced numbers.

BacterLab ensures the quality of each product batch by testing with ATCC reference strains.

Reference strains	Incubation conditions	Expected results
Salmonella typhimurium ATCC 14028	18 – 24 hours, 35 – 37°C	Good growth
Eschirichia coli ATCC 25922 (subculture on MacConkey)	18 – 24 hours, 35 – 37°C	Partial to complete inhibition