A method is described of determining the susceptibility of enterobacteria to four amino-glycosides by means of an antibiotic diffusion method. The results are expressed as the minimal inhibitory concentration (MIC) of antibiotic and were compared with those obtained by a method that involved titration in agar plates and the use of a multi-point in-oculator. A statistical analysis showed that the diffusion method gave accurate reproducible results.

The antibiotic can be incorporated into paper disks, paper strips or agar ditches and the calculation converting the measured zones of inhibition to MIC values is easily performed. The appropriate equation is derived from another-obtained from observations on a single strain of known sensitivity-describing the diffusion of the antibiotic from the reservoir.


Article metrics loading...

Loading full text...

Full text loading...



  1. Cooper K. E. 1963; The theory of antibiotic inhibition zones. In Analytical microbiology edited by Kavanagh F. London and New York: p 1
    [Google Scholar]
  2. Ericsson H. M., Sherris J. C. 1971; Antibiotic sensitivity testing: report of an international collaborative study. Acta Path. Microbiol. Scand Suppl 217
    [Google Scholar]
  3. Farrell I. D. 1969; The use of antibiotics and antibacterial agents fo the selective isolation of Brucella abortus. Ph.D. Thesis University of Liverpool;
    [Google Scholar]
  4. Robertson L., Farrell I. D., Hinchliffe P. M. 1973; The sensitivity of Brucella abortus to chemotherapeutic agents. J. med. Microbiol 6:549
    [Google Scholar]
  5. Stokes E. J. 1975; Clinical bacteriology, 4th ed. London p 217
    [Google Scholar]

Data & Media loading...

Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error