Question

In the past, students who have had organisms grow all over a Mueller Hinton plate without any antibiotics, but then they don’t grow at all on a plate when we include antibiotic disks. How would you interpret this? On the chance that you interpreted this as it being incredibly susceptible to one or more of the antibiotics – how would you go about discovering which one?

Answer 1

When growth is not shown after addition of antibiotic disks. It indicate that microbes which grew earlier are susceptible to these antibiotics but the question is to which or to which combinations of antibiotics. This can be deduced by plating microbial culture of same with different antibiotic in different petriplates. And then checking for growth, after that combinations of antibiotics can be made to be introduced in plates to check result of antibiotic combination of microbe growth.

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