Minimum Inhibitory Concentration (MIC) and

Minimum Bactericidal Concentration (MBC) Assay

Minimum Inhibitory Concentration (MIC) assay

Minimum Inhibitory Concentration (MIC) assay tests for antimicrobial susceptibility and sensitivity by measuring inhibition of growth of bacteria or fungi as a function of concentration. Emery Pharma routinely provides antibiotic susceptibility testing services using disc diffusion, agar dilution and broth microdilution MIC methods according to CLSI protocols (Check out our MIC guide in the resources section). Test articles can be natural or synthetic, mixtures or purified. Hundreds of bacterial strains, including multi drug-resistant clinical isolates, ESKAPE pathogens, and multiple fungal strains, are available in our inventory for immediate testing.

Below is an illustration of a panel representing Broth Microdilution MIC for 8 antimicrobials tested against a susceptible bacterial strain:

Minimum Inhibitory Concentration (MIC), 96-Well Plate

Minimum Bactericidal/Fungicidal Concentration (MBC & MFC)

Minimum Bactericidal Concentration (MBC) or Minimal Fungicidal Concentration (MFC) is the lowest concentration of an antibacterial drug that results in a 99.9% reduction in the initial microbial density. EP routinely performs antimicrobial effectiveness testing services which normally includes MBC (minimum bactericidal concentration) / MFC (minimum fungicidal concentration) in conjunction with MIC (minimum inhibitory concentration) to distinguish if antimicrobial compounds are bactericidal or bacteriostatic.

Below is a schematic representation of MIC and MBC assays for a test article:

Minimum Bactericidal Concentration (MBC) Assay
  1. As shown, the test article is serially diluted in the presence of bacterial inoculum, and the MIC demonstrates the lowest concentration of the test article that inhibits the bacterial growth. At this dilution the test article is bacteriostatic.
  2. MBC is the lowest concentration of a test article required to kill 99.9% of an initial bacterial inoculum. At this dilution the test article is bactericidal.