In the MIC assay, why did it matter what the E. coli density is? (Why was...

In the MIC assay, why did it matter what the E. coli density is? (Why was a diluted culture used to inoculate the broths?)
The MIC assay measures inhibition, not killing. If you wanted to conduct a Minimum Lethal Concentration, how could it be done?

Expert Solution

The culture for the MIC assay is taken to be diluted in order to allow equal distrubution and effect of the antibiotic used. If the concentration of the antibiotic is less but the bacterial cukture is much more cocentrated, the appropriate effect of the antibiotic won't be observed as there will chances if antibiotic degradation

Minimum lethal or minimun bactericidal concentration is the concentration of the antibiotic that totally kills the bacteria. The MIC is the concentration at which there is no growth observed in the test tube but when plated in the antibiotic less plates, a few dormant colonies grow. The next concentration of antibiotic containing culture that shows no growth in the test tube nor in the agar plates, is the MBC or MLC. For example, if the antibiotic concentration for MIC is 8ug/ml but when plated it shows a few colony growth. The next concentration, say suppose, 16ug/ml shows no growth in test tube nor in the antibiotic free agar plates is the MBC

gladiator answered 1 year ago

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