Fluid Thioglycollate Medium (FTM) is a complex medium designed for the cultivation and isolation of fastidious aerobic and anaerobic microorganisms present in sterility test samples of pharmaceutical industry.
The anaerobic atmosphere is created by reducing the redox potential of the medium by Thioglycollate and L-Cystine. Additionally, these compounds inactivate mercury and other heavy metal elements present in the environment. The presence of beef extract adds to the carbon source and other essential vitamins in the medium to support the growth of microorganisms present in the sample.
The presence of agar may reduce the rapid diffusion of oxygen and lead to slight turbidity in larger volumes (filled bottles). Resazurin indicator in the medium indicates the reduction potential. An increase in oxygen concentration is indicated through a color-change reaction to pink.

Fluid Thioglycollate Medium (FTM) is mainly used as a sterility testing medium for sterile pharmaceutical samples. to cultivate and isolate anaerobic and microaerophilic microbes.