Aerobic and anaerobic bacteria
can be identified by growing them in liquid culture:
(oxygen-needing) bacteria gather at the top of the test tube in order to absorb maximal amount of oxygen.
2: Obligate anaerobic
bacteria gather at the bottom to avoid oxygen.
bacteria gather mostly at the top, since aerobic respiration is the most beneficial one; but, as lack of oxygen does not hurt them, they can be found all along the test tube.
gather at the upper part of the test tube but not at the top. They require oxygen but at a low concentration.
bacteria are not affected at all by oxygen, and they are evenly spread along the test tube.
Fluid thioglycollate media or thioglycollate broth is a multi-purpose, enriched, differentiating media used primarily to detect the level of oxygen requirement of various microorganisms. Sodium thioglycolate in the medium consumes oxygen and permits the growth of anaerobes. This, combined with the diffusion of oxygen from the top of the broth produces a range of oxygen levels in the media along its depth. The oxygen concentration at a given level can be indicated by a redox sensitive dye like resazurine that turns pink in the presence of oxygen.
Thioglycollate broth medium is recommended to isolate strict anaerobes
should an anaerobic infection be suspected.
This allows differentiation of facultative and obligate aerobic, anaerobic, microaerophilic organisms based upon growth at various levels in the media.As an example, anaerobic Clostridium will be seen growing only in lower portions of the media.
Thioglycollate broth is also used to recruit macrophages to the peritoneal cavity of mice when injected intraperitoneally. It recruits numerous macrophages, but does not activate them.
- ^ http://ftp.ccccd.edu/dcain/CCCCD%20Micro/thioglycollatebroth.htm
- ^ Cheesbrough, Monica (2006). District Laboratory Practice in Tropical Countries, Part 2. Cambridge University Press. p. 126. ISBN 0-521-67631-2. Retrieved 2009-09-14.
- ^ a b Leijh PC; van Zwet TL; ter Kuile MN; van Furth R (November 1984). "Effect of thioglycolate on phagocytic and microbicidal activities of peritoneal macrophages". Infection and Immunity 46 (2): 448–452. PMC 261553. PMID 6500699.