Science Buddies: "Ask an Expert"

For my science fair project I wanted to see how probiotics and pathogenic diseases interact with each other and if probiotics can act as a sort of antibiotic. To test this I wanted to grow a strain of e. coli by itself in a petri dish, then I wanted to grow the e. coli with different types of probiotics (probiotic, capsules, yogurt, and kombucha). This is where my question comes in. I am unsure how I should grow these bacteria with each other. Should I simply spread a layer of the e. coli in the petri dish and then a layer of the probiotic on top or should I do bleep like the Kirby-Bauer test? Any help would be appreciated.

Hi there,

This sounds like an interesting experiment! I think the Kirby-Bauer test would be the best option. Using that bleep would help to make sure you are adding the same amount of each probiotic to the E. coli and it will make it easier to quantify your results. This project guide has instructions on how to do the Kirby-Bauer test https://www.sciencebuddies.org/science- ... medication

If you have more questions, don't hesitate to ask!