Test
Test
Test
- Inoculate the sample onto the culture plate according to the relevant protocol.
- Do not expose the plates to light, and incubate them at 35 degrees Celsius for 18-24 hours.
Results and Interpretation
Shigella colonies on this culture medium appear raised, green, and moist. Salmonella on this culture medium forms green-blue colonies that may have a black center. Coliforms also form orange-pink colonies on this medium. Colonies suspected of being pathogenic should be subjected to further testing.
Note
- Proteus species may have colonies similar to Salmonella and Shigella, so it is recommended to
use biochemical, immunological, and molecular tests for accurate diagnosis.
- The presence of antimicrobial agents in the samples inhibits or delays the growth of bacteria. In addition, the presence of these agents can change the appearance of organisms in the culture medium.
- To accurately isolate enteric pathogens, it is recommended to use liquid enriching selective media such as GN Broth or Selenite Cystine Broth in addition to solid selective media.
- The bile salts in this medium crystallize over time and form spider-web-like patterns, but this does not affect the medium’s performance.
- Sometimes during the transfer of Hektoen Enteric Agar culture plates, the green color of the agar may turn into brown. This is a normal occurrence and will not have any effect on the test results.
