Selenite broth
Selenite broth is used as a selective medium for the isolation of Salmonella species. Selenite Broth was originated by Leifson, 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 | 4g/l |