A laboratory test measures the lowest concentration of an antibiotic that completely inhibits visible bacterial growth after 18–24 hours of incubation. This concentration is termed the:
- A Minimum Inhibitory Concentration (MIC) ✓
- B Minimum Bactericidal Concentration (MBC)
- C Zone of Inhibition diameter
- D Post-antibiotic effect (PAE)
Correct answer: A. Minimum Inhibitory Concentration (MIC)
Explanation
The Minimum Inhibitory Concentration (MIC) is defined as the lowest concentration of an antimicrobial agent that prevents visible growth of a microorganism after overnight incubation. MBC is the lowest concentration that kills 99.9% of organisms. The zone of inhibition is a qualitative/semi-quantitative measure from disc diffusion, not a concentration. PAE refers to continued suppression of bacterial growth after antibiotic levels fall below the MIC.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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