Disc Diffusion (Kirby-Bauer) Antimicrobial Susceptibility Testing

In this video you’ll learn the principle of the Kirby-Bauer disc diffusion test and see how it is performed and interpreted.

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[ABRIL]

Did this last week for my micro lab class .

[besa_milo]

The video is so helpful, Thank you so much ❤️

[Christamariadahdouh]

Thanks this helped. I didn't think that there was a machine that could tell the McFarland of a tube. WOW. Since we are in practice, we just use a random amount. BUT, i guess, it is best to add more then less since you did take colonies twice from agar and into saline.

[Sfxxs]

Hi, I want to compare the effectiveness of commercial antibiotics and natural antibiotics. I am planning to use the Kirby Beuer method. However I am confused on which step I should use the antibiotic treatment. I really need an answer, thank you!

[Khaledf]

Thank you. Is there a specific medium used for this test? Can we use nutrient agar? 😊

[suchonasmriti-orcn]

Hi...
I am completing my test according to the EUCAST guidelines and strictly follow the 0.5 Mac Farland standard visually.
But After incubation No inhibition is obtained.
What are the issues?
1.Antibiotic disc CAZ-30...is it lose it’s effectiveness??
2. Or Is Bacteria be strengthen Against Bacteria?
Please Help me.
I have tried the test about three months.
Finally I am failed.

[nhatminhtran]

Hi I want to ask that can I test antibacterial activities of solid sample by this method, for example ZnO nanoparticle

[babusheikh]

Hi there, please help! I am conducting the antibacterial assay of my plant sample following the well diffusion method. But I have faced with a problem. Should I filter my plant sample with the help of 0.2 micron filter inside laminar flow cabinet before adding the samples into the wells. I found that when I filtered my sample, the concentration as well as the volume of my prepared sample also get decreased. I have also gone through severe literatures of my field but found no paper mentioning the use of 0.2 micron filter. So is it necessary to do so or I can skip this step?

[TheRedKnight]

I am using blank disks and disks where only solvent is added as a negative controls, Yet I still get small zones of inhibition for both. Are these zones okay as long as they are a standard diameter? Or is there an issue with how I am plating the disks or time between making the bacterial lawn and adding disks?

[chinasaezeiru]

Hi what was that red medium in your petri dish

[jeffronylpausal]

hello! may i ask what kind of agar did you use for culturing in this video? we are going to perform disc diffusion method on p. acnes and we are suggested to culture it in fastidious anaerobe agar specifically blood agar. if so, would the new plate which we will transfer our p. acnes on during the disc diffusion still contain the blood agar?

[abdullahfrehat]

please i want to ask you, it is normal to use paper disk that submerged with specific antibiotic ? to test the effectivness of other antibiotic ?

[Jjannaa_.]

sir if the outcome was resistant does that mean the treatment was weak?

[tanigirl]

I'm doing fungal research study these days. We couldn't find perfect method to test antifungal activity. Can't we do disk diffusion method on fungi

[salmaallah]

Do you incubate the plates upside down

[malvikasingh]

I did swabbing but instead of uniform growth, there were only scattered bacterial colonies on the media.. Can anybody explain why it happened?
What precautions should be taken while doing swabbing to get uniform growth?

[Thinker-gdck]

Hi Dr.Rubin, it seems you replied my questions, but I couldn't see the reply.

[jozefinachadzynska]

Hi where can I find interpretive criteria for Lactococcus?

[Thinker-gdck]

Hi, May I ask you how to access CLSI on VET08 ED4? I could not find it.