Selenite broth is used as a selective medium for the isolation of Salmonella species.[1] Selenite broth was originated by Leifson,[2] while observing good recovery of Salmonella spp. and reduced growth of fecal coliforms. Selenite broth is used as a selective enrichment for the cultivation of Salmonella spp. that may be present in small numbers and competing with intestinal flora. This medium must not be autoclaved. Once prepared it is steamed at 100°C for 30 minutes. There should be a very slight red precipitate. To minimise the risk of teratogenicity to workers, sodium selenite must be added separately to the medium. It has a pH of approximately 7.1. Selenite broth gives pale or colourless colonies.
Selenite broth contains:
| Peptone | 5g/l |
| Mannitol | 4g/l |
| Di-sodium hydrogen phosphate | 9.5g/l |
| Sodium di-hydrogen phosphate | 10g/l |
| Sodium selenite (NaHSeO3) | 4g/l |
References
- ^ Orden, B; Franco, A (August 1993). "Wellcolex Colour Salmonella Test and Selenite-F broth". Journal of Clinical Microbiology. 31 (8): 2249–2250. PMC 265738. PMID 8370763.
- ^ Leifson, E. (1939). "New selenite selective enrichment medium for the isolation of typhoid and paratyphoid bacilli". Am. J. Hyg. 24: 423–432.