Bismuth sulfite agar

From WikiMD's Food, Medicine & Wellness Encyclopedia

Bismuth Sulfite Agar is a type of agar used as a selective and differential medium in microbiology. It was developed by Wilson and Blair in 1927 to isolate Salmonella typhi, the bacteria responsible for typhoid fever.

Composition[edit | edit source]

Bismuth Sulfite Agar contains bismuth sulfite, beef extract, dextrose, ferric citrate, and brilliant green. The bismuth and sulfite in the medium inhibit the growth of most bacteria other than Salmonella. The brilliant green dye also helps to inhibit the growth of other bacteria, making the medium highly selective.

Uses[edit | edit source]

Bismuth Sulfite Agar is primarily used for the isolation of Salmonella species, especially Salmonella typhi. It is also used in the identification of other Enterobacteriaceae.

Procedure[edit | edit source]

A sample is streaked onto the surface of the agar and incubated at 35°C for 24 hours. If Salmonella typhi is present, it will grow as black or greenish-black colonies. Other bacteria, if they grow at all, will produce colonies of a different color.

Limitations[edit | edit source]

While Bismuth Sulfite Agar is highly selective for Salmonella typhi, it may also allow the growth of some other Salmonella species and a few other types of bacteria. Therefore, additional tests are usually required to confirm the identity of the bacteria.

Safety[edit | edit source]

Bismuth Sulfite Agar should be handled with care as it contains bismuth sulfite, which can be harmful if inhaled or swallowed.

Bismuth sulfite agar Resources
Doctor showing form.jpg
Wiki.png

Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD


Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro) available.
Advertise on WikiMD

WikiMD is not a substitute for professional medical advice. See full disclaimer.

Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.


Contributors: Prab R. Tumpati, MD