[Agar tube method for the bioassay of antibiotics (author's transl)]

A simplified bioassay system for antibiotics has been presented. Glass tubes with open ends and pits are filled with agar medium containing test microbes by immersing vertically into the agar medium while it is warm. These agar tubes are inserted in test solutions and incubated. The growth-inhibitory zones appear in respective tubes due to upward diffusion of the antibiotic. The heights of such zones from the bottom of agar tubes are measured.