Strict Anaerobes: Thioglycollate Broth
Thioglycollate is a broth or semi-solid medium which permits the
growth of strictly anaerobic and microaerophilic as well as aerobic organisms.
The reducing agent, sodium thioglycollate, maintains a low oxidation-reduction
(Eh) potential in the depths of the column of medium for long periods of time.
The medium should be heated to near boiling within 24 hours of use to drive off
any oxygen that has been absorbed. The caps on the media should be kept tightly
closed and the media
should not be agitated to minimize oxygen
absorption.
In thioglycollate, most anaerobes grow only in the lower portion of the tube
since some oxygen is usually present in the surface layers of the medium. Strict
aerobes grow only at the surface of the medium and facultative anaerobes grow
throughout the tube.
