How to determine whether zone of inhibition is due to death of the bacteria or its inhibition?

If the compound you are testing is bacteriocidal, you will not be able to recover

bacteria from the zone of inhibition. If the compound is only bacteriOStatic, you

should be able to recover bacteria from the zone of inhibition by scraping the

surface of the agar and resupending the scrapings in sterile saline and then

spreading an aliquot of the suspension on nutrient agar that does not contain

the bacteriOSttic agent.