PURPOSE:
- TraceMedia™ Mueller Hinton Horse Blood Agar is used for testing antibiotic susceptibility or MIC on challenging microorganisms like Neisseria, Haemophilus, and Helicobacter pylori.
PRINCIPLES:
- TraceMedia™ Mueller Hinton Horse Blood Agar contains a nutrient-rich composition, including beef extract and acid hydrolysate of casein, which provide essential amino acids, compounds, vitamins, and minerals necessary for microbial growth.
- The presence of starch acts as a protective colloid against harmful substances in the environment. Additionally, the medium contains a small amount of thymidine and thymine, and the concentration of divalent cations in the medium is controlled during antibiotic susceptibility testing on Mueller Hinton Agar. Agar solidifies the medium. The inclusion of Horse Blood enhances the growth capability of challenging microorganisms.
READING RESULTS:
- After the required incubation period, observe the growth of colonies on the plate’s surface and around the antibiotic disks. For identification of isolated bacteria, conduct further appropriate tests. If separate colonies are still visible, re-test is necessary.
- Invert the plate, hold it up to the light, and use a caliper to measure the complete inhibitory zone diameters (including the antibiotic disks). Read the zone edge from the area where bacterial growth is not visible to the naked eye.
- If the bacteria have faint or small colonies at the edge of the growth inhibition zone, they should be ignored. For interpretation of the inhibition zone, refer to CLSI M100 guidelines for each bacterial strain.