Be sure to change pipette tips after each transfter and mix the contents of each well. Add 2-5 ml of nutrient broth to each well and inoculate with the test bacterium. Cover the wells with parafilm and incubate for 24 hr. Check for growth . Check the bottom of the wells for a pellet of growth.
Growth is shown by a white dot in the bottom of the well.
Incubate for 24 hr. and record the presence of growth. If growth occurs in a subculture, the dilution was not bactericidal. Click here to check your answers. If you do not reach the MIC or MBC, change the dilutions and try again. Developing Resistance You can estimate whether resistance to the antimicrobial will develop quickly with the following procedure.