What is an antibiogram?
Antibiogram Test can be used for two different purposes. The Kirby-Bauer method is used to test the susceptibility of the bacterial strain to various antibiotics. Antibiograms can also determine minimal inhibitory concentration (MIC) or the least antibiotic concentration that inhibits the growth of a bacterial strain by dilution.
Kirby-Bauer method is an antibiogram used to determine the best antibiotics for use against specific bacterial stress. Tests are performed in Petri bowls that are shallow, round, covered with food filled with agar medium or gel substance filled with nutrients to promote bacterial growth. The bacterial tension to be tested is evenly spread over the surface of the plate. Several circular paper discs, each filled with a different antibiotic, are evenly distributed over the surface of the plate and gently pushed down into the agar to contact the bacteria. Plates can then grow overnight in Incubator.
After incubation overnight BThere is a circular surface without bacterial growth to surround every paper disk. This area is called an inhibition zone. The diameter of the inhibition zone for each disc is measured and compared with a control graph to determine whether the tested bacterial strain is resistant, medium or susceptible to each of the different antibiotics. A large inhibition zone would mean that the bacterial strain is susceptible to antibiotics on the test disc.
The dilution method is an antibiogram used to determine the most effective concentration of antibiotics to use against bacteria. It begins with cultivating or growing a fresh dose of the test bacteria overnight and then checking new cultures in terms of purity or cleaning culture. Two control or comparative bacteria are also prepared. The concentration of bacterial stems is determined by the use of a spectrophotometer and the concentration is adjusted to the range suitable for the dilution method.
serial dilution of antibThe iOTik to be tested is prepared by increasing and graded changes in concentration in different bottles. One series of different antibiotic concentrations is inoculated by the same amount of test bacterial strain and the second row is vaccinated by control bacterial strains. All inoculated antibiotic concentrations can grow overnight in the incubator or until visible bacterial growth in some bottles is observed. MIC is an antibiotic concentration where no visible bacterial growth is observed. The MIC value is a controlled way to assess the changing resistance of bacterial strains and set the limits of antibiotic therapy of infections.